Error message stops Win XP reinstall:The procedure entry point GetIiums could not be located in dynamic linc library MS DAR1.dll

I have been having problems getting on the internet for weeks, and worked with MSN for hours..  They said my problem was probably in my Windows XP Home software. I opted to reinstall (not clean install) win xp and when it was almost finished it gave the above message. 

At the top of the message box, "Unregmp2.etc  Entry point not found."

After waiting for awhile, the computer finished reinstalling on its own and the computer will still not connect with the internet.The modem appears to be fi ne and  dials robustly

Does anyone know what the message means and how that file might be repaired?  might a cleab install not have the same problem?