I WAS WORKING ON A SPREADSHEET WHEN SUDDENLY I GOT AN ERROR MESSAGE AND CLOSE THE SHEET. WHEN I OPEN THE SHEET AGAIN I FIND IT EMPTY AND I GOT A MESSAGE "Object reference not set to an instance of an object" HELP PLEASE. ENVIO MI HOJA DE CALCULO.Diseño a corte.sm (1 МиБ) скачан 9 раз(а).

The file loads without issues for me.

With SMath closed, you can try to open the %appdata% folder (write it in the windows address bar and hit enter) and then rename the SMath folder to something else (f.e. SMath_old), then launch the worksheet again and load the required extensions. If nothing changes you can revert everything by deleting the new SMath folder and renaming the old folder to its original name