I was using LR earlier today. Had to turn off and unplug computer because of a storm that came thru. I have turned it back on and tried to open LR and it wont open. It says it cannot be opened because it is not valid!! Please help! Need to get into it and finish a job!!
Let us know the exact error message word by word you are getting on the Lightroom Launch.
Else, try and reset the Lightroom preferences.
Press the shift + option keys immediately after you restart Lightroom, and select Reset Preferences from the resulting dialog box.