win 7 x64 BSOD crash on Word x64 save

[gliderpilot]

I am running Win 7 Pro x64 with SP1 v.721 on i7 3.07GHz with 16GB ram on my Desktop workstation
Installed Office 2010 x64
When I save a document to a second drive on the system Win 7 crashes with BSOD, not always the first time but after two or three saves
Tracked the crash to mup.sys
Disabled mup.sys and Word will save fine to the second disk without a crash but the computer cannot register on the network or see any other network resources
This only happens on Word save not with any applications
I would really like to be able to save documents and use the network resources

Dump file 020711-26598-01.dmp


Crash time 07/02/2011 19:45:12
Bug Check string SYSTEM_THREAD_EXCEPTION_NOT_HANDLED
Bug Check code 0x1000007e
Parameter 1 ffffffff`c0000005
Parameter two fffff880`01b87c3e
Parameter three fffff880`035544d8
Parameter four fffff880`03553d30
Caused by driver mup.sys
Caused by address mup.sys+4110
Processor x64
Full Path C:\Windows\Minidump\020711-26598-01.dmp
Processor count 8
Major version 15
Minor version 7601
Dump file size 286,408

Also when I save from Word on a laptop to the the desktop the desktop crashes with BSOD. Happens with x32 versions of Word also and earlier 2003 version.

Would really appreciate some help here.