Hi Funchess, Wesley,
Thanks for reaching out to Microsoft Q&A.
When you use the certificate import wizard to import a certificate and it indicates that the import was successful, but you still cannot open the encrypted file, there are a few steps and considerations to follow to troubleshoot and resolve the issue.
Note: All these suggestions might help you to fix or atleast narrow down the issue and in the belief that you are entering the correct password associated with the encrypted file.
Verifying Certificate Installation:
- Check Certificate Store: After importing the certificate, ensure that it is in the correct certificate store. You can do this by opening the Microsoft Management Console (MMC) and adding the Certificates snap-in. Check both the "Personal" and "Trusted Root Certification Authorities" stores to see if your certificate is listed there.
- Correct Store: If the certificate is not in the expected location, it may have been imported into the wrong store. Ensure that you are looking in the right place based on how you imported it (e.g., Local Machine vs. Current User).
Re-importing Certificate:
- Re-import the Certificate: Sometimes, re-importing the certificate can resolve issues. Make sure to select the correct store during the import process. Right-click on the certificate file, choose "Install Certificate," and follow the prompts to ensure it goes into the correct store.
Check File Encryption:
- Encryption Method: Confirm that the encryption method used for the file matches the certificate you imported. If the file was encrypted with a different certificate or method, you will not be able to open it with the newly imported certificate.
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