Have you tried Launching Lightroom and holding Ctrl+Alt during this Launch?
Usually Launch issues for Lightroom are either Activation or Catalog problems.
Most often Catalog, so trying with a New Catalog you can determine whether the problem is coming from Catalog, or from Activation.
Hope this helps.
I Am sorry i don't fully understand what you mean.
Could you explain a bit more clear?
If you would like to know how to get this screen:
Launching Lightroom and holding Ctrl+Alt during this Launch
Otherwise if that is not working for you, you can create a new file on your desktop
(start it as Text file as example) Rename the file with extension .lrcat (for instance: test.lrcat)
Double click the file, you should get an error, That lightroom can't read the file,
and if you would like to select a different catalog or would like to create a new one.
When creating a New one, Lightroom should launch (If the problem is catalog related).