Question

Using C# I am developing an Excel add-in. This add-in opens a Windows Form and needs to set ScreenUpdating to false so I am using the following code.

using Excel = Microsoft.Office.Interop.Excel;
[...]
ExcelApp = Globals.ThisWorkbook.ThisApplication;
ExcelApp.ScreenUpdating = false;

So far this works fine. However Excel locks up when closing the form and I don’t know why. When removing the following lines then closing the form is successful.

ExcelApp = Globals.ThisWorkbook.ThisApplication;
ExcelApp.ScreenUpdating = false;

Answer 1

Setting ExcelApp.ScreenUpdating = true; before closing the form solves the problem.