hmmm...well I for one have had no issues with SP1, SP2 or SP3 conflicting with file sharing...
DrTCP windows tcp tuning and tweaking - dslreports.com , do some research on it and what it does, use it and see if windows has some hosed settings for TCP/UDP...
as a note, in general I install service packs while doing a reformat and clean install of the OS, but with SP3 I didn't, and as noted have had no issues...
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So Long and Thanks for All the Files
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