User Name Capitalized

[mark350]

Unknown to me, my programmers had my forum set up where people were not able to choose a user name with capital letters. I have two questions:

1. Is there a setting in vbulletin admin to define user name parameters in regards to capitalization?

2. Is there any way I can take a user name such as "mark350" (lowercase m) and change it to "Mark350" (uppercase M) without causing any problems to any of the previous posts made by "mark350"? ... and can I do this in such a way that it would automatically change the user name "mark350" to read "Mark350" where it appears on various posts?

Thanks in advance for any help.

[Opserty]

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

If there is something in that box, that is what is probably causing your problem. You could either get it edited or remove it completely.

2) This would probably require a custom script, I don't think its possible with default vBulletin.