System hangs on startup trying to load AFD.SYS

[dbookbinder]

My XP home system hangs on startup at least 50% of the time. The bootlog ends with multiple attempts to load AFD.SYS, which according to the file's Properties dialog box is an "Ancillary Function Driver for WinSock."
I have multiple entries in the ntbtlog.txt file like the following, and that's where the log ends:

Did not load driver AFD.SYS
Did not load driver AFD.SYS

Even when the machine boots successfully, this particular driver seems peculiar -- it loads, then Windows attempts to load it again. The log looks like this:

Loaded driver \SystemRoot\System32\drivers\afd.sys
Did not load driver \SystemRoot\System32\drivers\afd.sys

Can anyone provide any insight into what might be causing the system to hang while trying to load this driver? This boot hang problem is incredibly annoying and time consuming.

Thanks,
David