IE & OE Lock Up

I am running windows 98 on a network with a T1 and IE6 and OE6. For some reason, at random times as soon as I click on the IE shortcut and the webpage begins to load, the PC completely locks up. This happens every once in a while when trying to read my mail in Outlook Express as well. This doesn’t seem to be a problem on any other machines on the network, just mine. Any ideas besides cleaning the Temp files, cache, and regular cleaning of the hard drive?