It's been a while since I messed around with SMB/CIFS on Windows servers, but IIRC you can force the server to downgrade the version of CIFS it will support. I remember having to adjust a server that needed to support older clients. Based on the comments from the post, it sounds like this is the problem.

A quick Googling turned up these:

Information about CIFS dialects: http://blogs.technet.com/b/josebda/archive/2012/06/06/window...

How to enable/disable specific CIFS versions: https://support.microsoft.com/en-us/kb/2696547