I'm having the same issue.
I had Lightroom 5 installed via CC, and working fine on a Windows 7 desktop.
I opened CC and saw the Lightroom CC upgrade.
I installed Lightroom CC,..but when I try to open it, it dumps and gives me the following error:
Adobe Photoshop Lightroom has stopped working
If I look at the problem details I see:
Problem Event Name: APPCRASH
Application Name: lightroom.exe
Application Version: 220.127.116.11
Application Timestamp: 5523190c
Fault Module Name: libcef.dll
Fault Module Version: 3.1750.1805.0
Fault Module Timestamp: 53eb9d68
Exception Code: c000001d
Exception Offset: 00000000020f5fa3
OS Version: 6.1.7600.2.0.0.256.1
Locale ID: 1033
Additional Information 1: 1849
Additional Information 2: 1849c65267ce2967d89f315e1c3c4b82
Additional Information 3: 95b7
Additional Information 4: 95b7e9ed49fb3657956fc9b27015606a
So what's up with this,...I'm at a dead stand still.
I have tried rebooting the desktop.
Signing out of CC and then signing back in,..to no avail.
I went to Adobe chat. They told me to sign out of Creative cloud and sign back in. It worked for me, but your problems sound a bit different. I hope you get it straightened out.
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