After deleting Digital Editions 2.0, 3.0 and 4.0 will not become the default epub reader in Win 7. Existing epub files have gone to unknown application. Digital Editions 3.0 and 4.0 app. will not load in, "open with" dialogue box. Some epub files load in initial install, but same files with unknown app to open, will not. Is Digital editions no longer a free app? I really need 2.0 back.
Solved my own problem. It was necessary to delete all instances of Adobe Digital Editions in programs and the registry. After doing so and reinstalling 4.02...., it became available in the "open with" dialogue box and became the default epub reader.