If your private key has somehow become public knowledge, you may want to revoke it so it can't be used to access a file any longer. Double-click the key/certificate you want to revoke and select "Generate Revocation Certificate." Once you do this, it can't be undone.So, if you have an encrypted file you need to access with the key, make sure you decrypt it before revoking access. Otherwise, the file will remain encrypted unless you already have a decrypted backup.