In the VBE, enter this in the immediate pane (ctrl/G):
application.Dialogs(xlDialogWorkgroup).Show
Deselect what you DON'T want, and then whatever you do in one workbook will
be done in both (all) for the selected sheets. If this is a duplicate post
(by me), it's because it seemed it didn't take the first time, so apologies!
Bob Umlas

"Clark" wrote:

I want to open two separate worksheet files in the same window, then make
changes in cells to worksheet 1, and have those same changes occur in
worksheet 2.