The AutoMount feature is enabled by default in W2K8/W2K8R2 on a systems without SFW installed:
"NoAutoMount" = "0"
SFW 5.1SP1 and SFW 5.1SP2 change the default automounting policy in Windows to off when SFW is installed on W2K8 in order to avoid various problems with Windows such as the Windows Format dialog popping up when a new volume is created even though SFW is already formatting the volume, snapshots automatically getting drive letters, etc.
So, after the SFW 5.1SP1/SP2 installation, the "NoAutoMount" changes the value to " 1".
The Windows SP1 wizard install for Windows 2008 requires the default automounting setting.
Please follow the instructions below to install the Windows SP1:
1. Go to on the passive node.
2. Change the "NoAutoMount" to "0". (This setting is needed by the SP1 install wizard).
4. Install the SP1 for Windows 2008.
5. Change back the "NoAutoMount" to "1".
Then failover all Cluster groups to the other node and repeat the above steps to the remaining node.