I'm using Access97 with crystal report 7. It works properly. But when i install it at any other place where Access2000 was installed. It gives an error "OLE AUTOMATION ERROR". What to do?

Other problem is that when i upgrade my system to Access2000 and remove it from add/remove program. Then install Access97 it gives an error "ACCESS VIOLATION". The problem is not solved until i format my heard disk. What is other option without format?