Mozilla Firefox

[Kazal]

Last year I had a guy out to my computer because it was running very slow,kept freezing etc and he took it away to clean it up and he also added a bit more Ram. It worked well for a week and then I was unable to get Internet Explorer, he came back out and put me on Mozilla Firefox. I have BT Broadband.
Recently when I log in to Mozilla I get a 'Page load error address not found',and then BT desktop help drops in and I have to go through the whole rigmerole every time to get on to MF. Also, when I delete e-mails the whole lot closes down and takes me to desk top and I get a page error from MF and have to start again.
I'm not very up on computers and was wondering if I can try to get Internet Explorer back, how do I do it and will it affect anything else .
I need an idiots guide by the way.

[VHG]

Internet Explorer is part of Windows so it will be included on any PC with Windows on it.

So open up the main "Windows" menu and look for Internet Explorer.

Select on it and the IE browser should open.

[Kazal]

Thanks for this, but will it affect anything else and do I need to delete MF?
Told you I know nothing about computers