how do i only allow letters and numbers, no spaces in usernames?

[azn_romeo_4u]

how do i only allow letters and numbers, no spaces in usernames during registrations.

[azn_romeo_4u]

Bumb

[azn_romeo_4u]

Bump Again.

I remember seeing a build in VB feature...or was I mistaken...now I can't find it.

[James Birkett]

AdminCP -> vBulletin Options -> User Registration Options -> Username Regular Expression

In the box put:

^[A-Za-z0-9]+$

This will allow A-Z capitals, a-z lowercase (even though user registrations are case insensitive) and 0-9, thus disallowing everything else.

[azn_romeo_4u]

Thank you sir.