Obscure SharePoint errors #13653: DavWWWRoot is not accessible

The scenario is: SharePoint… open in Windows Explorer is working great and then mysteriously, BOOM, it no worky no mo.

\\server\DavWWWRoot\etc is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions.

A device attached to the system is not functioning.

Except it does worky on other places, even in the same site. Screams of permissions issues…. but it’s not.

It’s actually the number of items in the library has now tipped over *yet another* threshold in SharePoint and this is the error. It’s all described here.

The fix is rather… ugly - yep, a registry hack:

Open Computer\HKLM\System\CurrentControlSet\Services\WebClient\Parameters and find FileAttributesLimitInBytes

Flip to decimal view and spank it up to something big. *NOTE* this DOES affect performance, so try and pick a sensible number… something that is broadly in line with what’s in the library.

Start / stop WebClient (net stop WebClient)

And Robert’s your Father’s bro. Hopefully.