Simion
5
Look in your spam folder for the Avast email containing your license key.
After Avast stops supporting 4.8 you might look into ClamWin AV and it’s real time/heuristic counterpart, Clam Sentinel.
Also, an active/helpful forum for Win98 users is at http://www.msfn.org/board/forum/8-windows-959898seme