For some users the solution was to sign out and sign back into the Creative Cloud application. (Note that it's not just exit and start again.) See if that works for you.
Unfortunately the issue is still unsolved for many of us.
I have it work! ( I have Windows 7 64bit system.)
1. I removed LR 2015 from Creative Cloud window.
2. I went to Control Panel - Programs and Feature tab and select stil showing Adobe Lightroom 6 and select uninstalle.
The reply was that program is already deleted and the line showing the program was cleared.
3. I disable Firewall (I have Vipre.
4. I went to web page of Adobe.com and Sign in; I select Desktop Apps and then select download of Lightroom 2015
5. The downloaded program name was "CreativeCloudSet-Up.exe"
6. I run this exe file. And all went nice and perfect
7. When LR 2015 open I select to open another catalog file ( not the ones suggested) from my current LR 5.7.
I hope this will work for you and some others
Thanks, I'll try this. Just to to check if I understood you well: You uninstalled Lr 6 from the CC app, downloaded a fresh installer of the CC app (not Lr as such) and installed that one?
BTW, that could be it as just before installing Lr 6 I had the CC app update itself. Maybe the issue is there and your solution fixes that. Here's hoping.
Yes . The problem I thing happen that my original message on CreativeCloud Window on my PC telling me that I shall install new Lightroom CC. The download was compromised by my Vipre Firewall.
Good luck and enjoy. The new LR CC and new LR on my Samsung tablet is great!
That didn't work for me. What happens when I run the downloaded .exe file is that it shows an initialization window and a couple of seconds later the CC manager app just shows. I don't think reinstallation with an existing CC manager is possible.