I am new to control toolbox toolbar combo boxes and check
boxes.

When I use a control toolbox combo box, I was wondering
why Excel thinks that the file has changed, that is the Do
you want to save changes question pops up when
opening/closing a file even though nothing has changed.

Another thing happens using a checkbox, where in a new
workbook I inserted a control toolbox check box. I right
clicked on it and selected view code, looked, didn't
change anything and closed file. Now when I open the file
Excel asks if I want to enable macros.

Can any one tell me what is happening here?