Restart your machine, and then try to open ADE.
thank you for the response.
I have done that (restarted my machine and try to open ADE) ... numerous times.
I certainly appreciate the suggestion. Do you have any other thoughts or guidance?
For anyone on a Windows machine having this issue -- after searching for what seems to be hours (and a few days) on this forum board, I've finally found a response that works, with a limp.
I've had to switch to ADE 3.0, unauthorized my computer, and reauthorize it.
The thread that assisted me was here:
The specific response that assisted me was this:
"When you uninstall 4.0 and install 3.0 you will have to deauthorize and then reauthorize your account and reader (CTRL+SHIFT+D) and it should work. This saved me a lot of anguish.
You can find the old versions here: Adobe Digital Editions downloads"
When I had ADE 3.0 open, I utilized the CTRL+SHIFT+D, which took me to a dialogue box that allowed me to "de-authorize" simply;
Then, I clicked on the Help pull-down menu, followed by a click on "Authorize this computer".
I'm now up and limping along able to access the two books that are about to have to be checked in.
For Adobe's information, I am still unable to "re-activate" ADE 4.0.3 -- and that's after adding all .exe's to my Firewall exceptions; among various other advanced attempts to resolve the issue. Is anyone from the "official team" going to be working on this?