1) What's your b2 version?

2) What link are you using to update the profile?

3) You are not supposed to call the below file directly.

http://b2evolution.net/htsrv/profile_update.php

4) You should use this link rather:

http://b2evolution.net/?disp=profile

I said I got it trying to update my profile on "this" site, meaning b2evolution's site, the profile connected with the user who is making this comment. So whatever version this site is using is the version.

I pressed the edit my profile, edited it, tried to save it, and it gave me the error originally reported.

@drherz we updated the software, are you still having trouble updating your profile?