If you happen to have Expression Blend 4 installed alongside the Expression Blend 4 for Windows Phone, you may find that the Context Menu looks something like this:
One of these things is not like the other. Which of the two “Microsoft Expression Blend 4” menu items do you choose?! The easiest way to differentiate between the two versions is, well, to click on one of them. Opening the Blend IDE only to find that it cannot recognize your solution can be time consuming. So, here is a quick registry location you may want to edit to fix that issue.
Open up your registry and search for the text that appears in the context menu, “Microsoft Expression Blend 4”. Which should lead you to the following location, eventually.
HKEY_CLASSES_ROOT\Local Settings\Software\Microsoft\Windows\Shell\MuiCache
You can see that all you need to do is edit the data for the key (at your own risk) and add something like “for Phone” to the name.
Then you get a much easier context menu to work with.

38505e71-7006-479b-ac08-fbc5f31d2e31|0|.0