Spreadsheet - Renaming Columns - Errormessage

[eried]

(03-19-2015 05:27 PM)Dirk. Wrote:  After renaming a column in the spreadsheet, e.g. the first column from ‘A’ to ‘Alpha’, it seems impossible to change the name back to ‘A’. There is only a message “Error: Invalid input”. Is there a simple workaround?

Select the cell and press DEL