Internet access after uninstall SP3

I needed to uninstall SP3 because of problems with a software package that I
use daily. After successfully uninstalling SP3 I can not access the internet
via IE 7. I am running XP Pro. Any ideas on how to resolve?? Should I try
to reinstall SP 3 and if so then what?? As I do need to remove SP3. I have
uninstalled SP3 on another machine without this problem.
.