Why LibreOffice keeps saying the document is locked for editing?

I created file LinuxNotes.odt some time ago and yesterday I edited that same file at my work place and I was in Guest account when I edited that file.

Now whenever I open that file any where else Ubuntu slap me with Document in Use error Message.

What's the cause?

Solution 1:

There should be a hidden "lock" file created by LibreOffice and, for some reason, not automatically removed when the document was closed.

Open the folder where the document is located and press Ctrl+H to show the hidden files, then search for a file with a name similar to your document file name, but starting with ".~lock.". Remove that lock file and you're done.