Save .jpg erases file from disk drive in Corel PHOTO-PAINT 2017


My Photo-Paint 2017 has started to behave weird: it allows to save a jpg-file only with a new name. If you try to save changes to an existing file (Save-dialogue) or try to replace the existing file with a file with the same name (Save As-dialogue) - it erases the file from disk. The file is saved only if it has a new name (which doesn't exist in this folder). I haven't had time to do extensive tests, but saving .tif files for instance works  as it should.

Can anybody help? I've lost several files already and probably will continue to as soon as I forget about it.