That's odd.... How did write this?
Ok, here's my similar problem. I'm using Opera, but I cannot log in to sprint with that. I mean it shows me lots of codings when I log in as if I'm a hacker lol.
I think what you need to do beside what shiki explain of what may happen is this.
Upgrade your mom's computer to Internet Explorer Window 8. Since it's Window Vista I'm sure you can. Then try to get Mozilla 3.5 (notice that it's not installed in your computer when you finish extract it)
Then you'll have access to all sites and server including this forum from your mom's computer. If you are using an Apple Mac try using only IE8.
Most sites does not support IE6, or IE7.