ValidateUsername problem Vanilla 22.214.171.124 and php 5.3.23 ?
I ran into a problem with php 5.3.23 and Vanilla Forums 126.96.36.199. Upon registration, users would get the error:
Username can only contain letters, numbers, underscores, and must be between 3 and 20 characters long.
regardless of whether they submitted a valid username or not. I found that the regex for validating usernames was having a problem:
produced the warning:
PHP Warning: preg_match(): Compilation failed: unknown option bit(s) set at offset 0
and $Matches would be NULL.
It looks like it was the u bit that was causing the problem.