Symptoms
- 'You need permission to perform this action' when opening a file or folder
- 'Access is denied' error copying or deleting files
- Problem appears after moving a drive from another PC or reinstalling Windows
- Only certain folders are affected, often user or Windows system folders
Likely causes
- CommonFolder ownership tied to a different Windows user accountMoving a drive between computers or reinstalling Windows changes account IDs.
- PossibleEncrypted with a different user's credentials (EFS)Files encrypted under another account may be unreadable without that account's key.
- PossibleRestrictive permissions inherited from system-protected foldersSome folders are locked down by Windows itself for safety.
What to do
- Right-click the folder, choose Properties, then the Security tab, and click Advanced.
- Click 'Change' next to the owner field and set yourself as the owner.
- Check 'Replace owner on subcontainers and objects' to apply it to everything inside.
- Under Security, edit permissions to give your account Full Control.
- If the files were encrypted (EFS) under a different account, you'll need that account's credentials or certificate to decrypt them.
- If ownership changes don't restore access, the files may need to be recovered under the original user profile instead.
When to call a pro
If files were encrypted under an account you no longer have access to, a professional may be able to help recover the encryption certificate, but success isn't guaranteed.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.