Carmaux 

If you want to stop/open the automatic close, you can manually disable/enable this option.

     Click File > Options.

     Click Advanced, and then under Editing options, select or clear the Enable autocomplete for cell values check box to enable or disable this option.

Additional link: Use AutoComplete when entering formulas

VBA:

To activate and deactivate certain areas I think VBA would be necessary.

Here is a quick macro with buttons to activate or deactivate.

Sub Workbook_Deactivate()
Application.EnableAutoComplete = False
End Sub

Sub Workbook_Activate()
Application.EnableAutoComplete = True
End Sub

In the attached file you can see it as an example.

I would be happy to know if I could help.

NikolinoDE

I know I don't know anything (Socrates)

Was the answer useful? Mark them as helpful!

This will help all forum participants.