Sound Card And Modem Problems

I have recently upgraded my home Computer from Win 95 to Win 98. Before this upgrade my modem and sound card worked fine. After the upgrade I cannot get either to work. I have gone through the Win 98 trouble shooting steps. I unloaded Win 98 and everything worked. With my modem I can here it open the phone line but it does not dial (I just here the dial tone). Some of the modem problems seem to coincide with trying AOL (while operating 95)and my modem never worked correctly after installing anduninstalling AOL. I cannot unload 98 the program to uninstall has vanished.