Using windows 10.Happens on all files as well as opening writer or calc. Clicking on start and finish completes the opening properly. But it is a pain to have to go through that to get it to open.
Here’s something that worked for me. Without LibreOffice open, go through your Documents folder and any sub-folders that you might have tried to save something to. You might see a file that begins with .~ (period, tilde) and ends with # (hash). These files appear when you have a document open; they should go away as part of LibreOffice’s normal cleanup procedures, but sometimes they don’t. See if that helps. If it doesn’t, you can restore the file out of the Recycle Bin.
Checked for .~ (period, tilde) and ends with # (hash) none with those markings. So I still have the problem.