I am running support for one of our VP's, so I don't have all of the complete details, but I will provide what I can. He is running Parallels 6 (latest patches that I am aware of) on Mac OS X Lion (also latest patches). Within Parallels is Windows 7 x86 with Office 2010. Again, I believe he has installed all of the patches to the guest OS and Office. He can run Outlook 2010 and for the most part everything is ok. However, he opens a new email and clicks the File Attach button and nothing happens. The file selection window never appears. Excel was doing something similar, but a restart of the app cleared that up. Outlook always does this. He can drag and drop an attachment with no issues or complaints. Windows users running Outlook 2010 do not have this issue, so I can only assume it's an issue with Parallels. Please let me know if I can provide any other details. I've not found any other posts or forums with people having this issue.