When I try to save a Calc file to a folder it changes it to an excel file and I can't open it.

[betteelou]

When I try to save a Calc file to a folder it changes it to an excel file and I can’t open it. I am saving it as a ODf (I think) file. To a folder on my desktop. What am I doing wrong?

[LeroyG]

When saving your files, select Files of type: ODS Spreadsheet (*.ods).

See more LibreOffice Help on Saving Documents.