Privacy & Security for Teams, Shared Drives & External Sharing: A Modern Guide

Protecting sensitive data isn’t just a technical challenge — it’s about trust. When your team collaborates through shared drives, cloud services and external links, your documents and conversations leave the four walls of an office and travel across services you don’t control. If a link gets forwarded to the wrong person or a laptop goes missing, confidential information can become public. Modern collaboration tools and file encryption software exist to mitigate those risks, but they only work when you know how to use them effectively. This guide unpacks practical steps for securing files and conversations in collaborative environments. It covers built‑in tools on Windows and macOS, locking photos and voice memos on iOS, and controlling access in Microsoft 365, Google Workspace and Dropbox. You’ll also learn how third‑party encryption apps (https://www.newsoftwares.net/) like Folder Lock can create tamper‑proof vaults for your most important files. Throughout the article you’ll see citations in brackets that link to authoritative sources; these show where the underlying information originates.

Understanding the risks of collaboration

Shared drives and cloud services are great for teamwork because they centralise files and keep everyone working on the latest version. The downside is that the same link that makes a file accessible for a colleague also works for a hacker if it leaks. Documents may contain financial data, customer lists or intellectual property, and they can be transmitted via email links, chat messages or mobile apps.

Why external sharing is risky

• Weak links in the chain: Many breaches occur because an external partner’s account is compromised. When you share a document with editing rights, you implicitly trust that user’s password and their organisation’s security policies.
• Over‑sharing: People often share entire folders instead of specific files. In SharePoint and OneDrive, external sharing can be allowed at both the organisation and site levels. If external sharing is enabled for a site, everything inside it is potentially accessible. Microsoft’s guidance notes that if you need to store confidential information, you should create a separate site where external sharing is turned off.
• Anonymous links: Guest links let anyone with the link access files without signing in. These “anyone” links can’t be restricted or revoked per user. Microsoft recommends turning off the ability to share with anonymous links or at least limiting them to view‑only.
• Persistent access: In Google Shared Drives, files belong to the team rather than individuals. Members who leave the organisation still leave their files behind, which benefits continuity but also means you must manage permissions carefully.

The human factor

Even when your IT policies are strict, human error can undermine them. Employees can share a link with personal emails, copy sensitive files to unencrypted USB drives or leave printed documents in the office. A layered defence combines strong technical controls (encryption, access rules) with training and guidelines. You should encourage staff to report suspicious activity and regularly review shared‑drive membership.

Built‑in tools for securing files and folders

Operating systems and productivity suites offer encryption features for individual documents and folders. Understanding these tools helps you choose the right level of protection for each use case.

Encrypt files and folders on Windows using EFS

The Encrypting File System (EFS) is built into Windows Professional and Enterprise editions. EFS uses your Windows account to encrypt files so they can be read only when you’re logged in. To encrypt a folder:

1. Right‑click the file or folder in File Explorer and choose Properties.
2. On the General tab select Advanced.
3. Check Encrypt contents to secure data and click OK, then Apply. Windows asks whether you want to encrypt just the file/folder or its parent folder as well.
4. If it’s your first time using EFS, back up the encryption certificate and key to a safe location. Avira’s step‑by‑step guide notes that you can export the certificate through the Certificate Export Wizard.

EFS is transparent in day‑to‑day use; when you open encrypted files, Windows automatically decrypts them. If someone copies the files to another computer or logs in with a different user account, the files remain unreadable. However, EFS has limitations: it is only available on NTFS volumes, it uses the user’s Windows account (so other administrators can override it), and it doesn’t protect file names. For portable protection, you may prefer third‑party tools like Folder Lock [https://folder-lock.com/] or BitLocker for whole‑drive encryption.

Protect Word documents, PDFs and Excel workbooks

Many documents live in Office formats or PDF files. You can add password‑based encryption from within the applications themselves.

Word documents

To encrypt a Word document:

1. Open the document in Microsoft Word.
2. Choose File › Info › Protect Document › Encrypt with Password.
3. Enter a strong password and re‑enter it to confirm. Microsoft notes that you must remember this password because there’s no way to recover it.
4. Save the document. From now on you’ll be prompted for the password when opening it.

Passwords can include spaces and symbols; choose a passphrase that mixes upper‑ and lower‑case letters, numbers and special characters. You can also restrict editing without encrypting the whole file (e.g., mark as final or restrict formatting), but full encryption offers stronger protection.

PDF files

Adobe Acrobat lets you password‑protect PDFs. In Acrobat:

1. Choose All Tools › Protect a PDF › Protect with Password.
2. Pick whether the password is required to view or edit the file.
3. Enter and re‑enter a password of at least six characters.
4. Apply the protection and save the file.

If you need stronger encryption or fine‑grained control, Acrobat allows you to set 256‑bit AES encryption and restrict printing and copying rights.

Excel workbooks and other files

Excel and other Office applications use the same mechanism as Word. In Excel, go to File › Info › Protect Workbook › Encrypt with Password, enter a password, confirm it and save. For PowerPoint presentations, choose Protect Presentation. Mac versions of Office include similar options under the Review menu.

Password‑protect compressed files and archives

Compressed archives (ZIP, RAR, 7z) are useful when you want to package a folder and send it over email or share it via a link. Windows allows you to create a basic ZIP file, but it doesn’t offer password protection. Third‑party tools such as 7‑Zip and WinRAR fill that gap:

1. First create a standard ZIP archive (right‑click the folder, choose Send to › Compressed (zipped) folder).
2. Open 7‑Zip, choose Add to archive…, select the file or folder, then choose 7z or zip as the archive format.
3. In the Encryption section, enter a password and select AES‑256 encryption.
4. Click OK to create the encrypted archive.

On macOS and Linux you can create password‑protected archives via the command line: zip -e archive.zip file1 file2 prompts you for a password. Because the encryption is file‑level rather than tied to your user account, recipients need the password to extract the contents.

Secure USB flash drives with BitLocker

USB drives are convenient for transferring large files and backups, but they’re easily lost or stolen. Windows includes BitLocker To Go for encrypting removable drives. To set it up:

1. Plug the USB drive into your PC.
2. Search for BitLocker in the Start menu and open BitLocker Drive Encryption.
3. Find your removable drive and click Turn on BitLocker. Choose Use a password to unlock the drive, then type and confirm a strong password.
4. Save the recovery key to a secure location (file, printout or Microsoft account) so you can unlock the drive if you forget the password.
5. Choose whether to encrypt the entire drive or just used space and select the encryption mode (compatible with older systems or only Windows 10/11). Click Start Encrypting.

Once encrypted, the drive requires the password each time it’s connected. If you need cross‑platform compatibility or advanced features, NewSoftwares offers USB Secure, which prompts you to select the drive and set a password.

Create an encrypted folder on macOS using Disk Utility

macOS doesn’t let you directly assign a password to a folder, but you can create an encrypted disk image (.dmg) that acts like a secure folder. Steps from Moonlock’s guide include:

1. Open Disk Utility (Applications › Utilities or via Spotlight).
2. Choose File › New Image › Image from Folder… and select the folder you want to protect.
3. Name the disk image and choose where to save it.
4. For Encryption choose 128‑bit AES or 256‑bit AES, enter a password and verify it.
5. Select read/write as the image format so you can add files later.
6. Click Save. macOS creates a .dmg file. To access the contents, double‑click the .dmg and enter your password. The original folder remains on disk unprotected, so you can delete it after confirming the disk image works.

This method provides strong encryption on any Mac and is suitable for archiving or transferring sensitive folders.

Lock photos and voice memos on iOS

Personal photos and audio recordings on your phone can leak during device sharing or syncing. iOS provides built‑in tools to hide or lock media:

• Hide photos/videos: In the Photos app select the items, tap More and then Hide. The files move to a Hidden album that doesn’t appear in the Photos view. Skylum notes that you can turn off the visibility of the Hidden album via Settings › Photos › Show Hidden Album. In iOS 16 and later, the Hidden album is automatically locked behind Face ID or Touch ID.
• Lock photos using Notes: Create or open a note, add photos via the camera icon, then tap the three dots and choose Lock Note. Set a password or enable Face ID/Touch ID so the note requires authentication to view.
• Unhide or remove: To unhide photos, go to Albums › Hidden, select the items and tap Unhide.
• Hide voice memos: Although iOS doesn’t offer built‑in locking for the Voice Memos app, you can remove the Voice Memos control from Control Center or use third‑party apps. A blog screenshot shows steps: open Settings, go to Control Center, tap Customize Controls, and remove the Voice Memos icon hollyland.com.

Collaborating securely with shared drives and external users

Businesses often rely on cloud platforms for teamwork, which can introduce complexities around permissions and guest access. This section explores major platforms and highlights policies and best practices.

Microsoft Teams, SharePoint and OneDrive

Microsoft 365 bundles Teams, SharePoint and OneDrive. Teams uses SharePoint for file storage and OneDrive for personal files. Security features include multi‑factor authentication, encryption of data in transit and at rest, audit logging and integration with Microsoft Purview for compliance. However, secure defaults still require configuration.

Controlling external sharing in SharePoint/OneDrive

SharePoint administrators can set external sharing policies at the organisation and site levels. Microsoft documentation emphasises that the most restrictive policy applies: if org‑wide sharing is set to “New and existing guests” but a specific site is set to “Only people in your organisation”, external sharing remains disabled for that site. Key actions include:

• Disable “anyone” links and limit sharing to authenticated guests.
• Store confidential information in sites where external sharing is turned off.
• Use sensitivity labels, which apply encryption and usage rights when a document travels outside your organisation.
• Restrict site members from further sharing: SharePoint allows disabling the site members can share setting so only owners can invite guests.

Best practices for Teams security

Teams acts as a hub for meetings, chat, calls and file sharing. To harden Teams:

• Enable multi‑factor authentication (MFA) and require strong passwords.
• Use conditional access policies to restrict sign‑ins based on location, device health or risk.
• Apply role‑based access control (RBAC): assign owners, members and guests deliberately; guests have limited capabilities and cannot create teams or channels.
• Limit external access: configure guest access and domain allow/block lists. Orchestry’s article suggests controlling app integrations, restricting screen sharing and enabling meeting lobby options to keep uninvited guests out.
• Implement data loss prevention (DLP) and sensitivity labels to detect and block sensitive data from leaving the organisation.
• Audit and update memberships regularly; archive or delete inactive teams to reduce exposure.

OneDrive external sharing and preventing sync

OneDrive for Business allows you to share files and folders with external users. To enable external sharing you need to adjust SharePoint policies and then share items:

1. In the Microsoft 365 admin center, go to SharePoint › Policies › Sharing and set the level to Anyone or New and existing guests.
2. In OneDrive, select a file or folder and choose Share. Enter the external user’s email, choose the permission level (view or edit) and send the invitation. If you allow “anyone with the link”, recipients without a Microsoft account will receive a verification code.

If you need to prevent syncing (for example, to stop a folder from replicating to a PC), you can pause or unlink OneDrive. The Cloudwards guide describes three approaches:

• Pause syncing: Click the OneDrive icon in the system tray, choose Help & Settings › Pause syncing and select a duration.
• Remove specific folders: Pause syncing; copy the folder to another location; delete it from your OneDrive; then resume syncing.
• Unlink this PC: In Settings › Account, select Unlink this PC to stop the computer from syncing altogether.

Google Shared Drives

Google Shared Drives (part of Google Workspace) store team files separately from personal Drive files. Key characteristics include:

• Team ownership: Files belong to the team, not individual contributors, so content stays accessible even if someone leaves.
• Role‑based permissions: Content managers can add or remove members and share folders; contributors can edit files but cannot share folders; viewers have read‑only access.
• External sharing restrictions: Shared Drives at Columbia University allow sharing only with “LionMail” accounts (institutional accounts), not personal Gmail. You can create limited access folders to restrict files within the drive so only specified members see them.

To remove access for someone leaving the project, go to Manage Members, locate the user and select Remove access.

Dropbox: password‑protecting shared links

Dropbox Professional and Business accounts let you secure shared links with passwords and expiration dates. You can disable downloads and require recipients to sign in. Dropbox’s documentation notes that recipients must enter the password to view or download the file, and you can enable two‑factor authentication for extra security.

Why Folder Lock is the best solution

While built‑in tools provide basic encryption, they can be cumbersome, limited to specific platforms and sometimes require administrative privileges. Folder Lock by NewSoftwares LLC offers a more comprehensive solution for personal and professional use. Here’s why:

• Proven track record: NewSoftwares has been developing Folder Lock since 2001. The app has over 55 million users and is trusted by institutions like HSBC, Dell, MIT and government agencies.
• Strong encryption: Folder Lock uses 256‑bit AES encryption for its lockers. On‑the‑fly encryption means files are secured as soon as you add them, and only decrypted after you enter the master password.
• Multiple protection modes: You can choose to lock folders (hide them from view without encryption) or encrypt them in secure lockers. Locked items are invisible in Windows, while encrypted lockers are accessible only with the password.
• Secure backup & cloud sync: Folder Lock can back up lockers to cloud storage with zero‑knowledge privacy. Your data is encrypted before it leaves your device, so even the company can’t access it.
• Portability: You can protect USB drives and write data directly into encrypted lockers, ensuring that files remain secure even when copied to other devices.
• Extras: Additional features include a file shredder to permanently delete files, a password wallet for storing credentials and credit cards and an optional stealth mode. These features aren’t available in EFS or BitLocker.

How to use Folder Lock

1. Download & install: Visit the official site (newsoftwares.net/folder-lock) and download the Windows version. No account creation is required; run the installer and follow the prompts.
2. Create a master password: When you first launch Folder Lock you will set a master password. Choose a long passphrase with uppercase, lowercase, numbers and symbols. The security of your lockers depends on this password.
3. Lock folders: Click Lock Folder in the interface, then drag and drop files or folders into the app or click Add Items to Lock. Locked items become hidden in Windows Explorer. This is quick for hiding large folders but does not encrypt them.
4. Encrypt files: To encrypt, choose Encrypt Files, create a new locker, give it a name, choose a location (local drive, cloud or USB) and set a password for the locker. Specify its capacity (it functions like a virtual drive). When you open a locker with your password, it appears as a new drive; drag files into it to encrypt them.
5. Back up & sync: If you want zero‑knowledge cloud backup, enable the Secure Backup feature. The app encrypts your locker before syncing so only you can decrypt it.

Unlike EFS, Folder Lock encrypts both file contents and names. It also works independently of your Windows login, which is helpful if multiple people share a PC. The one drawback is that there is no native Mac or Linux version, but you can access lockers via the portable version on a USB drive.

Comparative overview of security solutions

The table below summarises common methods for protecting files and folders. It includes built‑in tools and third‑party solutions. Remember not to put long sentences in the table; it should be quick to scan.

Method	Platform	Key Features	Limitations
Windows EFS	Windows Pro/Enterprise	Encrypts file contents tied to user account	Requires Windows account; not portable
BitLocker To Go	Windows (USB)	Encrypts entire USB drive with password	Windows‑only; must remember recovery key
Word/Office encryption	Windows & macOS	Encrypt individual Office files via password	Password required each time; easy to forget
PDF password (Acrobat)	Windows & macOS	Set password for viewing/editing PDFs	Requires Acrobat (paid for advanced)
ZIP encryption (7‑Zip)	Windows, macOS, Linux	Password protect archives with AES‑256	Third‑party software; archives only
Mac Disk Utility (DMG)	macOS	Create encrypted disk image (.dmg)	Original folder remains unless deleted
Folder Lock	Windows	Lock or encrypt folders; secure backup; shredder	No Mac/Linux version
Google Shared Drive settings	Google Workspace	Control external sharing and roles	Restricted to organisation; not file‑level encryption
Dropbox password link	Dropbox	Password‑protected shared links	Pro accounts only; link can be forwarded

Secure sharing practices and troubleshooting

Even with strong encryption and platform controls, human error can jeopardise your data. Here’s how to minimise risks when sharing internally and externally:

• Use unique share links for each recipient: Don’t reuse generic “anyone” links. Assign each external partner a separate invitation so you can revoke one without affecting others.
• Set expiration dates and passwords: For Dropbox and some OneDrive shares, set an expiry date and add a password. This ensures the link won’t work indefinitely and prevents accidental reuse.
• Enable multi‑factor authentication (MFA): Protect accounts with an additional verification step. Teams and SharePoint support MFA for all users.
• Review permissions regularly: Periodically check who has access to shared drives. In Google Shared Drives, use Manage Members to remove individuals who no longer need access. In SharePoint, you can stop sharing or change links anytime.
• Educate your team: Ensure everyone understands the difference between “view” and “edit” permissions, the risks of sharing with “anyone” links and the importance of strong passwords. Provide guidance on creating passphrases (e.g., longer than 12 characters with a mix of character types).
• Backup your keys and passwords: For EFS and BitLocker, back up recovery keys to offline storage. If you lose the key or forget the password, data may be irretrievable.
• Test your recovery plan: Periodically test that you can unlock encrypted files and restore backups. This ensures your security measures are effective and you know the steps under pressure.

Frequently asked questions

1. Can I password‑protect a folder on Windows without software? Yes. On Windows Pro and Enterprise, you can encrypt a folder using EFS by selecting Encrypt contents to secure data in the folder’s properties. However, this ties the encryption to your account. For portable encryption across devices, use BitLocker or a third‑party tool like Folder Lock.
2. How do I share a OneDrive file securely with an external user? In OneDrive select the file, click Share, enter the person’s email and choose Anyone with the link or Specific people. If allowed, you can set a password and expiry date. The recipient may need to verify with a one‑time code.
3. What’s the difference between locking and encrypting in Folder Lock? Locking hides the file or folder from Windows Explorer but doesn’t encrypt the contents. It’s quick for privacy when you’re near your PC. Encrypting creates a locker that uses 256‑bit AES encryption so even if someone copies the locker file, they can’t open it without the password.
4. Is it safe to use Dropbox to share confidential files? Dropbox Professional and Business accounts allow password‑protected links and expiry dates. Combine these with strong passwords and multi‑factor authentication. For extra confidentiality, encrypt files locally before uploading.
5. Can I retrieve a lost BitLocker password? You can unlock a BitLocker drive using the recovery key that you saved during setup. Without the password or recovery key, the data is effectively lost.
6. How do I remove someone’s access from my Google Shared Drive? Go to the shared drive in Google Drive, click Manage Members, find the user and select Remove access. They will no longer see the files in the drive.
7. What should I use to encrypt files on a Mac? Use Disk Utility to create an encrypted disk image (.dmg) with AES‑128 or AES‑256 encryption. If you prefer a cross‑platform solution, create a password‑protected ZIP using 7‑Zip for Mac.
8. Does Word encryption work on Mac? Yes. Office for Mac includes the option to password‑protect documents under the Review or Tools menu, similar to Windows.
9. How can I hide my voice memos on iPhone? Remove the Voice Memos control from Control Center via Settings › Control Center, or use a third‑party app that supports password protectionhollyland.com.
10. What if I need to share a confidential folder with multiple colleagues? Use a secure platform such as SharePoint or Google Shared Drives. Assign specific permissions (view or edit) to each person rather than using a public link. Consider encrypting the folder with Folder Lock before uploading it for additional security.
11. Is Folder Lock better than BitLocker? They serve different purposes. BitLocker encrypts entire drives and is integrated into Windows, while Folder Lock lets you lock or encrypt specific folders, offers secure backup, file shredding and a wallet and works without administrative rights. For comprehensive file‑level security, Folder Lock is often more flexible and user‑friendly.
12. How do I prevent colleagues from re‑sharing a document? In SharePoint or OneDrive, disable the option for members to share at the site level. In Google Shared Drives, choose role‑based permissions; contributors cannot share folders.
13. Can I use the same password for multiple encrypted files? Avoid reusing passwords. If someone discovers the password, they gain access to all your protected files. Use a password manager to generate unique, strong passwords.
14. What is AES‑256 and why is it recommended? AES (Advanced Encryption Standard) is a symmetric encryption algorithm widely used across the industry. AES‑256 uses a 256‑bit key, making brute‑force attacks impractical with current computing power. Tools like Folder Lock, BitLocker and 7‑Zip support AES‑256 encryption.
15. How can I tell who has access to my Teams or Shared Drive files? In Teams and SharePoint, go to File › Manage access to view who has permission. In Google Drive, click the Share button and look at the list of people with access. Review this list regularly and revoke permissions for those who no longer need them.

Conclusion

Digital collaboration doesn’t have to mean giving up control over your data. By understanding the risks of external sharing and using the right tools, you can keep your documents safe while still working efficiently with colleagues and clients. Built‑in features like EFS, BitLocker, Disk Utility and Office encryption provide baseline security, while third‑party solutions like Folder Lock via www.newsoftwares.net offer advanced protection with user‑friendly interfaces and cross‑platform options.