For SharePoint 2010, myOne way I've managed to work around this problem was that I was tryingis to "Open with Explorer" something that probably can't be opened with Explorer. In my case, I just wantedswitch from Standard View to open my team's Shared Documents with Explorer. I found that when I first log into SharePointDatasheet View and view the page, I'm presented with those Shared Documents, but also other things as well.
To get "Open with Explorer" to work, I mustthen click "Shared Documents" under the Libraries heading on the left. Then, all the other stuff (Links, Getting Started, etc.) go away and I'm focused on my team's shared documents. From there, I can go up to the Library Tools section in the ribbon, choose the Library tab in the ribbon, and click Open with Explorer.
Update: In an ever-changing corporate environment, you may find that one day this works and the next, it doesn't button. =\