XF 2.1 User getting erroneous error message when registering

[Stuart Wright]

He has reported that he can't register because of the error below.
Clearly he is entering a user name.

 

[Ozzy47]

Did you try with all addons disabled and on a default style?

 

[Stuart Wright]

Nope. To do that, I would have to effectively take the site down (it breaks considerably when our editorial addon is disabled) and then ask the person to try again.

 

[Chris D]

This won't be a bug, unfortunately, Stuart.

This isn't something I can reproduce in normal conditions so it will be a case of troubleshooting it perhaps with your host or by way of backtracking any recent changes.

 

[Stuart Wright]

I'll run through it with him on Skype. I haven;t had any other reports like it, but you've got to admit that there's something not right in this instance.