One common challenge that users face is encountering the error message Excel cannot open the file because the file format or file extension is not valid .

If you receive Cannot open the Clipboard error message when clicking or copy-pasting cells in Excel, take a look at your addins first and then use these fixes.

Tips You can convert OpenOffice.org text documents to Excel with the text import tool. Save the text document with the .txt file extension, open it in Excel and save it as an Excel spreadsheet.