As designed Email address with a ' in

Chris D

XenForo developer
Staff member
I had to actually check that was even a valid character in emails.

It looks to be valid. But it's possible that our validation tool, does not accept it. Unfortunately, our validation tool is part of Zend Framework and therefore not something we can change easily.

Incidentally, our email validation in XF2 doesn't accept it either. This applies to the ’ character and the ' character. Both of which, I believe, should be valid.

The only thing I can recommend right now is for them to use a different email address and I will move this to bugs.


XenForo developer
Staff member
Short answer here is that we aren't going to change anything here. There is a limitation within PHP that can be triggered in certain scenarios that causes a single quote to potentially be a security issue. We have blocked them (and are stripping them in other places) as multiple layers preventing this issue.