How to fix Excel not allowing to copy data from one worksheet and paste into another worksheet within the same workbook?

Software | Microsoft Office

By supporting this issue, most people were helped by this Solution.

Open the worksheet (ex. Sheet1.xlsx)

Select the "File" -tab.

Click "Advanced".

Enable (or disable) The "Lotus compatibility Settings for: Sheet1.xlsx" by enabling (or disabling) the options:

"Transition formula evaluation" and "Transition formula entry".

Click "OK".
Microsoft Office, Excel, Lotus compatibility Settings, Transition formula evaluation, Transition formula entry