during boot Ndis2 driver & Network Transport Driver not found
 

Cannot surf the net through my DSL router connection
because while booting, Ndis2 driver & Network Transport
Driver not found. I reinstalled the ndis2 driver from
local list of drivers, and re-booted, but same prob. Then
I downloaded from Microsoft list of drivers using my ISDN
connect, and re-booted, but same prob. What to do? In both
cases, system requests use of Win98 CD since it cannot
find a dll file. Suggestions? How could this happen in the
first place, since my connection was working fine until
this error during boot a few days ago?