I tried the following suggested possible fix but that didn't do the trick:
"Howdy Nukers,
I had the same problem as you were having, so I spent some time fingering around with some DB settings. It turns out that the DB may not be fully storing your password. The default value for storing a password is 20 characters. That isn't enough character storage if you have a big password, and not only that, your password gets encrypted, which adds more characters to it. A simple solution it to go into your database with an application such as phpMyAdmin and follow these steps:
- Note: This was performed in v6.5 with phpMyAdmin
1. Scroll down your table list and look for nuke_popsettings, and click browse.
2. Click on structure.
3. Scroll down the field list to passwd and click on change.
4. Edit the Length/Values number and give it a higher number, such as 60. I used 100 since I use real long passwords.
5. Save your changes.
6. Go back into WebMail and go to your account settings and re-enter your password so it gets fully recorded.
I hope that helps you out."
This was from http://www.nukecops.com/postp21076.html