Photoshop Elements - Can no longer save files

When this started I don't know.  I don't use photoshop every day but sometime in the last month.

If I open a photo, edit it and then try and save or save as I get the error "Could not save file as \\...\test.jpg because the file is already in use or was left over by another application.  Have had a look on line and people used to have this problem (2013) but I couldn't find the fix for it anywhere.

The only application open is Outlook which is always open and has never been a problem (tried closing it... made no difference). Have checked under Task Manager and there is nothing open/using this file.  The software is useless if if I can't save anything.

Help!