Tried opening my catalogue which I have been using without an issue, and today I'm getting the attached error message. There is no lock file. I have tried updating my software, I have also attempted creating another catalogue and importing the catalogue, to no avail. It appears there is zero file size in the catalogue. Please help!
If the file size is zero, then it is not a valid catalog, and there is nothing to open.
You should restore the catalog file from your backups.