Why might my wireless internet connection not be working?

[366]

I recently tried reinstalling my Telstra Bigpond 7.2 Mobile Card Wireless Broadband USB on my home PC after I had to wipe the HDD due to a string of annoying virus attacks. My computer is perhaps 6-7 years old, I think (not sure what model, as I think it was assembled custom in a shop).

I reformatted/wiped the HDD using my Windows XP Home Edition disc & reinstalled the OS, with it now running on Service Pack 1.

I managed to install the Bigpond mobile card fine, & it even connects alright, but when I try opening Internet Explorer it doesn't even connect to the default Bigpond homepage.

Interestingly though, it seemed to be working fine when I initially went to Windows Updates to try & upgrade to Service Pack 3, etc. although it cut out when it got to searching for relevant updates for my PC, and since then I can't actually do anything in Internet Explorer.

Tried looking through Internet options, but I'm not really familiar with that sort of thing, & couldn't make head or tail of it.
Should probably also mention that when I was reinstalling the OS, it did ask me about internet connections, but decided to skip it because I don't understand what type of connection I have with my wireless broadband.

Any suggestions on what the problem may be or how to fix it would be greatly appreciated!

[406]

Possible reasons why your wireless Internet connection is not working:

→You incorrectly followed the instruction to install the Wireless Internet device
→Weak Internet connection

Good luck!