Support » Plugin: UpdraftPlus WordPress Backup Plugin » Decryption failed…but key NOT wrong. Website offline for days…

  • Resolved Random Dev


    Hi David. UpdraftPlus is mostly fabulous and I really appreciate it! One (very critical) thing I haven’t appreciated, though, is the inability to upload/decrypt encrypted databases. Both myself and my Web host have been working at this for two days straight and just can’t figure it out. I get the error:

    Decryption failed. The most likely cause is that you used the wrong key. The decryption key used: [actual-key-here]

    HOWEVER, I *know 100%* that the key is correct because I’ve only ever used the one, and I saved it to a file just in case. So what other likely causes could there be?

    Not sure what info I need to give you to offer suggestions – please let me know. It’s urgent that I get this site back up and running quickly. Thanks for any help you can offer.

Viewing 5 replies - 1 through 5 (of 5 total)
  • This was because I was trying to restore a backup from a different WP installation (from “test” subdomain installation into new, “root” installation).

    Once I purchased “Migrator” add-on, it restored/imported AND decrypted with no problems. Whew!

    I didn’t realize you couldn’t do the above. Having that clearly added to the plugin documentation may save other users a lot of time, frustration … and emotional anguish. 🙂

    Thank you so much.

    Plugin Author David Anderson


    Hi chumpchangewd,

    That’s very odd. The Migrator add-on doesn’t have any code that interacts with the encryption or decryption; 100% of the encrypt/decrypt code is in the base plugin.

    We’ve never before seen or had a report of a failed decryption with the right key, so would be very interested if you get any more information on it.


    Hey David, thanks for your response. Happy Thanksgiving/holiday.

    It was failing because it came from a different WP install. Are you saying that’s not normally how it works / it doesn’t normally stop you from importing/restoring a database to a different WP install?

    For instance, I had two installs: one root install (, one “test” subdomain install (

    I had the plugin installed on both. Test install was to, well, “test” a new theme and its functionality. Once satisfied that all was working well, I backed up the “test” install for the last time, deleted the root install, then attempted to restore the backup files from the “test” install to the root.

    At that point, all else restored (plugins, “other,” etc.) EXCEPT the database, which gave the error:

    “Decryption failed. The most likely cause is that you used the wrong key. The decryption key used: [actual-key-here]”

    No one could figure this out for two days, including myself as webmaster / designer and numerous tech support agents at a highly capable host. I finally deduced that, though keys were the same, perhaps it was failing BECAUSE they were from two different WP installs. That was exactly it.

    Plugin Author David Anderson


    > That was exactly it.

    But, that can only have been incidental, as the encryption and decryption code takes only two inputs: 1) the data to be encrypted/decrypted and 2) the key. What “site” the data is from (whether that means the site URL, or anything else) isn’t one of the inputs.

    This can be seen in the stand-alone PHP file that’s provided for decryption, here:

    I’ve personally decrypted various database backups that people have sent me, both using the stand-alone code, and using the in-page drag/drop decryptor.

    So, there must be some other subtlety involved…


    Thanks for sharing. I’d actually figured the same thing, that it shouldn’t matter if the key was identical; I was simply grasping at straws by that time. 🙂

    I don’t know why it didn’t like me, but at least it’s sorted now. Thank you again for your response and the plug-in. It really is awesome! (Especially now that I feel that I fully understand its idiosyncrasies. ;-P) Take care.

Viewing 5 replies - 1 through 5 (of 5 total)
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