"Error! check activation" message

Hi, 

I have Windows 10 and I've tried to delete key file but I can't delete autoritation in Adobe Digital Editions yet, and I can't open my new ebooks.

Maybe is something about the time or date of my pc, and my phone but I don't know.

Someone can help me?

Thanks

This solution was posted by someone else and worked for me:

Close all applications.

    Choose Start > Run.

    In the Open text box, type regedit and then press Enter. The Registry Editor opens.

    In the left pane of the Registry Editor, locate the following registry key: HKEY_CURRENT_USER\Software\Adobe\Adept

    Select the Adept key.

    Choose File > Export.

    In the Export Registry File dialog box, select Selected Branch under Export Range. Enter a name and location for the backup registry key, and then click Save.

    Right-click the Adept key and choose Delete.

    In the Confirm Key Delete dialog, click OK.

    Close the Registry Editor.

    Open Adobe Digital Editions and reauthorize.

The above did NOT work for me but below is what did.

Success!!!!!

None of the prior steps helped me at all.  However, what I just did that worked was to delete ALL versions of ADE on my computer and reinstall version 4.0. 

I had updated from v3.0 to v4.5.2 to deal with the ASCM files type but got in the same endless loop of failure to authorize or failure to connect to authentication server, both errors (falsely) suggesting I was not connect to the internet.

The registry editing, DE-authorizing/re-authorizing, shutting down windows firewall/Norton antivirus etc. just cycled me through these error messages without solving the problem. 

I don't even know when v4.0 was downloaded or if it was automatic at some point, but by uninstalling v3.0 and v4.5 and selectively installing v4.0 everything worked the way it should.

I must say I found the chat people with whom you connect when you click the Help tab in ADE was worthless (actually worse than worthless since the snarkily pointed out it was free if necessary software and therefor not supported) and the Forum articles simply cycled me through useless and sometimes scary (deactivating all my PC's security features) steps without resolving the problem.

V4.0 works as it should.   Now I just have to figure out how to assure it will not auto-update and put me back in server failure hell.

Hope this helps others.  Good Luck out there...

Don't know why the top of this post says "This question is not answered"??  After downloading the new version of ADE and following Nanaky's instructions, I am finally back in business.  I'm thinking that the "new and improved" Overdrive does not play nicely with the "old" ADE, so following all of the above and additionally uninstalling the old ADE certainly worked for me,

Thank you, Nanaky.

Thank you also.  Registry key fix worked on my "check activation" error after I installed version 4.5.2 of ADE after I started getting #2038 error message on my old version 1.7.2 ADE.

Yes, it worked.

Now if only we could get Kobo and ADE 4.5 to work to gether reliably, we'd be in business (like many, I had to downgrade to 3.0 in order to be able to copy library books from authorised ADE to authorised Kobo without "anauthorised" message when trying to read the book on the Kobo). It really is strange that they have been unable to figure it out in two years!

Windows:

    Close all applications.

    Choose Start > Run.

    In the Open text box, type regedit and then press Enter. The Registry Editor opens.

    In the left pane of the Registry Editor, locate the following registry key: HKEY_CURRENT_USER\Software\Adobe\Adept

    Select the Adept key.

    Choose File > Export.

    In the Export Registry File dialog box, select Selected Branch under Export Range. Enter a name and location for the backup registry key, and then click Save.

    Right-click the Adept key and choose Delete.

    In the Confirm Key Delete dialog, click OK.

    Close the Registry Editor.

    Open Adobe Digital Editions and reauthorize.

Macintosh:

    quit Adobe Digital Editions.

    Navigate to /Users//Library/Application Support/Adobe/Digital Editions and drag the activation.dat file to the trash.

    If you are using 10.7, see https://helpx.adobe.com/x-productkb/global/access-hidden-user-library-files.html

    Open Adobe Digital Editions and reauthorize.