Windows 7 Service Pack 1 (SP1) and Windows Server 2008 R2 SP1 clients that are configured for SMB1 don't respond to oplock break requests on stream files. This causes file access problems and application issues. A stream file is identified by the "file:stream" notation, as in the following example:
This issue does not occur when you're using SMB2, the default Server Message Block (SMB) protocol that's negotiated by Windows 7 and Windows Server 2008 R2). Additionally, this problem does not occur with Windows clients that natively use SMB1, such as Windows XP and Windows Server 2003.
f1:s1
Because Windows Server platforms do not support oplocks on stream files, this problem occurs only during a connection attempt to a non-Microsoft SMB product that does support oplocks on stream files over SMB1. This issue does not occur when you're using SMB2, the default Server Message Block (SMB) protocol that's negotiated by Windows 7 and Windows Server 2008 R2). Additionally, this problem does not occur with Windows clients that natively use SMB1, such as Windows XP and Windows Server 2003.