I had an user with email "xxxx_xxx@xxxxx.xx".

If she go to the "Preferences" and just press the button "Edit preferences", without changin anything in the profile, there is an error appearing, that e-mail isn't correct.

I found, that the reason is in the "_" symbol in her email. Is it possible anywhere to change that allowed symbols ?

I tried this with my email in my board and haven't received any error...

"_" is used very often in the email addresses.

vitalyb
You may have this error because current email has to be changed is already registered by another user or admin.

Syntax of email address is checked in bb_func_checkusr.php

Team, thanks, that is it.