Finally got 4.51 to open. Next problem: E_adept_request_expired. Here's what I've done:
1. uninstall ADE
2. export Adept reg key
3. delete same reg key
4. reboot
5. re-install 4.5 as admin; install details show "completed"
6. open ADE, library view
7. ctrl-shift-D to delete activation; no message, so not activated
8. associate acsm and epub files with ADE
9. download NEWLY requested epub library book, today's date, time and time zone
10. click on acsm file: opens ADE and requests authorization
11. attempt with Adobe ID and Overdrive ID: error msg: E_adept_request_expired
12. authorize without ID doesn't work
13. create Adobe ID and I forgot password don't work and freezes the app.
I can manually add an epub book and read it in ADE, no problem, so the program is working, the activation seems to be blocked, probably on my end.
What step can I next try?
thanks,