Browser service not working

Hi all. I've got an XP computer here that can access the internet via ping/tracert/etc but will not access the internet with the browser...either IE or Firefox. There was a virus which started this whole thing, we fixed it and the system is clean of all malware. After a lot of searching, it appears that the browser service is not running. Computer had SP2 on it, installed SP3 on it, no change. Other than unable to use Firefox or IE to get to the net, the computer is completely normal.
Any suggestions are welcome, and thank you in advance.