Lightroom 6 won't load

[Aydiaman]

I upgraded to Lightroom 6 from 5.7 6 months ago.  Today, Lightroom 6 has seemingly disappeared from my hard drive.  It shows up in the control panel uninstall panel.  OS is Windows 10.  I can open 5.7 version but I have an extensive library on Vers 6 that I have spent countless hours on.  The error message states "unexpected error opening catalog"  Need assistance please.

[JP Hess]

Are you getting this error when you try to start Lightroom 6? Or, is it when you try to start Lightroom 5.7?

[Aydiaman]

When I attempt to open Lr 6

[John Waller · Accepted solution]

Suggestions from Adobe

Error: "Unexpected error opening catalog" occurs in Lightroom after Windows 10 upgrade