Libre Office has stopped working correctly

The above is the message Windows 7 returns before closing L.O. When re-opened L.O. recovers the Workbook but Windows closes L.O. with the above message if I select the “Solar” tab or attempt to “save” or to “save as” the recovered file. Also the same if I attempt to delete the “Solar” tab.
This happened yesterday and I ended up abandoning that file and updated a version saved last week with the new information. All appeared to be well but again this morning the re-created file is not usable. None of it.
Libre Office on Windows 7. Suspect the problem is long formulae (95? values) in that “Solar” tab. I will make a test file to attempt to check that but if that does not crash will be stuck with submitting the full 1506 Kb file.

Further Comment:
I put the “unusable” file on a USB stick and opened it with Libre Office on Windows 10 on a laptop computer and it works properly there.