I am in the process of upgrading the server that Backup Exec runs on.
I created the Software Encryption Key a while ago. I am not 100% sure I remember the pass phrase. The only way I saw that I can test to see if I have the right pass phrase is to delete the key. Problem is if I'm wrong then I'm out of luck.
Is there another way to test the pass phrase?
There is no way to recover a passphrase. Anyone using Encryption should document their passphrases and store that documentation in a safe location.
If you are not sure what the passphrase is, you may want to replace the encryption key by following the steps documented in this article: https://www.veritas.com/support/en_US/article.100017836
This has been discussed here too: https://vox.veritas.com/t5/Backup-Exec/Encryption-Key/td-p/534565