It appears that some installations of Microsoft Office for Mac 2011 are either bitten by a bug, or the SP1 installer is faulty in that both the DMG and the auto-update versions fail to install stating the proper software was not found for updating. I attempted this on an iMac and hackintosh pc with 10.6.3 and 10.6.7 with the same result. I have previously updated Office 2011 without issue, but this SP1 seems to be broken. Has anyone else experienced this?
I found this very (un)-helpful link that also shows this is happening to others: