You need to include the sheet name in the instruction

Sheets("Sheet3").CheckBox1 = True

"Will" wrote:

My Excel workbook has several worksheets,
each of which contains several OptionButtons, CheckBoxes etc.

What I am looking for is a Macro, which runs from one worksheet
and which changes (enables, disables) the
OptionButtons/Checkboxes/etc. in the other worksheets.

Is this possible?

I have tried commands like
OptionButton1.Enabled = False
but I am geting "runtime error 424 -- object required".