restoring a catalog from backup issues

I don't mean to butt in here, but there are a couple of things that jumped out at me that may need to be addressed.

Gil said:

something happens and the catalog is not displayed on PSE so I had to restore it from backup.

You have not described the problem that originated your search for an answer here.  You may want to make sure that this original problem does not reoccur with any backup you may have.

Gil said:

this means instead of having a catalog of 600GB on an internal folder, now I have almost 1000GB folders. and of course, the restore process is failing as I have not enough storage.

I just want to make sure that you are not confusing the catalog with the media that is referenced therein.  According to system info., your catalog is 600MB, not GB.  The catalog is not normally contained within the same folder or sub-folder(s) as your media folders.  At least, I don't think it would be good practice to set it up that way.  However, the backup folder does contain both the catalog AND the media files which can then be restored to the original location or a new one if need be.

"note that working with external storage is irrelevant to me."

Then, the idea of a backup is meaningless?

What happens if something goes wrong with your computer? Stealth, fire, flood, hardware or software crash, user destructive error? How do you move your catalog to another computer or restore after a critical operating system update?

Can you describe your system and main drive type?

You can post here the first 15 lines of the dialog you get from the menu Help >> System Information in the organizer.