LR error message

[franks4308035]

After several years of good results, when I open LR classic the following message appears

Tried many times with no results to reboot etc.  Is there any help?

[dj_paige]

Go to the folder that contains your catalog file. In that folder is a subfolder whose name ends with Previews.LRDATA. Delete the subfolder whose name ends with Previews.LRDATA. Do not delete anything else.