I upgraded Ubuntu 16.04 to 18.04. Calc will not open any existing Spreadsheets.

I upgraded ubuntu 16.04 to 18.04. Now Libreoffice Calc will not open existing spreadsheets. Libreoffice Writer will open documents no problem.

How do you open your table? Start LibreOffice and then open the file from LO?

I cannot open any spreadsheets from within Calc. Calc will also not open a spreadsheet that it has just recently created. Calc just freezes up and eventually I have to cancel out of it. — However i can go into “Files,” click any spreadsheet and those will open successfully in Calc. — It is just within Calc that the spreadsheets cannot be opened. By the way, all of the spreadsheets are .xlsx files.

In Calc, I click the down arrow by “Open” files icon at the top left of the screen. I choose a spreadsheet from the list, an .xlsx file, but it never displays, the program just hang up.

Eventually I get the message, “LibreOffice Calc is not responding” Then I can choose “Force Quit” or “Wait”

You can try to reset your user profile. It is described here:
https://wiki.documentfoundation.org/UserProfile
otherwise you can also try to download and reinstall LibreOffice from the original source.Original source from here:
https://www.libreoffice.org/

Ok. I reinstalled Libre office from the software center icon and the Calc problem is fixed. Thanks.