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On our 2008 R2 domain, I have a strange entry in the list of folder replica.

\\?\C:\Windows\SYSVOL\domain      dc1       Enabled      SYSVOL Share
C:\Windows\SYSVOL\domain          dc2       Enabled      SYSVOL Share
C:\Windows\SYSVOL\domain          dc3       Enabled      SYSVOL Share
C:\Windows\SYSVOL\domain          dc4       Enabled      SYSVOL Share

While everything seems to work fine, I'm trying to decided if the first entry is something I should worry about.



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up vote 2 down vote accepted

The \\?\ notation is primarily used to work around the MAX_PATH limit, allowing a path length of up to about 32767 chars. Some Windows API functions have a Unicode version that supports that notation, some don't. My guess is that dc1 is either a more recent OS or a higher service pack or patch level than the other DCs, and that MS rewrote either the NTFRS code or a library used by the NTFRS code to support \\?\ notation for the new version.

Clicky for info.

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All 4 DC's are Server 2008 R2, installed from scratch so it's replicating with DFS-R rather than NTFRS. It's a pain that you can't google for \\?\ – Stephen Woolhead Oct 21 '09 at 21:04

The "\?\" notation is valid. I'm not sure why your machine is listing it that way, but it's perfectly valid.

Explorer doesn't seem to like that notation, treating it as a UNC, apparently. CMD.EXE likes it fine, thought. Try doing a "dir \?\C:\WINDOWS" (or some other valid directory) from a CMD prompt on one of your Windows PCs and you'll see what I mean.

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Does the SYSVOL share automatically just replicate over all domain controllers? – Kyle Brandt Oct 21 '09 at 19:17
Yes. It's a domain distributed filesystem root that is added to all DC's automatically. – Evan Anderson Oct 21 '09 at 19:26
Feel much more relaxed now! \\?\c:\ seems to work fine in explorer in 7/2008R2. I shall leave it as is. – Stephen Woolhead Oct 21 '09 at 21:11

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