Username error

Hi.

I got this strange problem with one of the users of my forum.

For somehow, he cant log in. Forum says either his username or password is wrong.
We have struggled with this for a few days. He tried getting the system to mail him a new password, (which it did), but still with the new password he cant log in.
I then edited his profile, given him a new password, and stil he is beeing rejected by the forum with the same reason: wrong username or password.

His username is: saltvand.
When he try to log in, he type saltvand in username and the password I gave him in the password promt. When forum says this error, then his username is changed in the promt to: vand

I then thought.. what the heck. I´ll edit his account entering my own email, and then ask for an new password using his username and the email (my own) I just entered. But this the forum reject as well, saying the email adress dont match his profile, (I just wrote my own email, so I´m damn sure of this, and when checking afterwards, it does say my email adress).

This leaves me with, something is very wrong with his username, but I just cant see it. In the admin menu, edit profile it says: saltvand. In the database it says: saltvand.

So whats wrong, and how can I fix it?

Unless you edited the register.asp page the forum should have come back with 'the username is already used' for any username that contains words like salt, admin, username, etc. so it should not have been possible to sign up with this usernmame.

You will have to ask the user to choose another username.