Hi James,
Thanks for your post. Generally speaking, the Encrypting File System (EFS) helps people encrypt files to prevent unauthorized access or virus attack. However, many people report a problem, especially after they updated the Windows system, that they receive error 0x80071771: This specified file could not be decrypted.
You should know that using the EFS to encrypt files requires the certificate if you want to access the file from a different computer. Here are some methods that may help you fix the error 0x80071771. You can try them one by one to find which fits your situation.
Method 1. Decrypt Files with the Command Prompt
You can access the file by giving the current account full permission. But this method doesn’t fit for files that are encrypted on a different device.
Method 2. Decrypt Files By Importing the Key & Certificate
Another way that allows you to access the encrypted files on a different device is by using the key and certificate. You need to export the certificate and the key from the original computer first then import them to the device where you want to access the file.
Reference: Fixed: The Specified File Could Not Be Decrypted (minitool.com)
Note: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it. Hope this helps.
Best Regards,
Ian Xue
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