Adding the same cell in all sheets

Hello. I have found following example:

This month I will show you some handy formulas used with a twist.

SUM ALL SHEETS

The first one is how we can use the SUM function to Sum, say cell A1, on all Worksheets in your Workbook. With this method, all new sheets that are added to the Workbook are included in the SUM. Here is how;

Add a new Worksheet to you Workbook at the far right. To do this select "Worksheet" under "Insert" on the Worksheet Menu Bar. Then left click on this new Worksheet name tab, holding down the the left mouse button drag to the far right and release.
Name this sheet (double click the name tab) "Spacer" (although any name will do).
With "Spacer" being the active sheet, go to Format>Sheet>Hide.
Repeat steps 1 to 3 above, but this time name the Worksheet "Start " and drag it to the far left.
On the Worksheet you wish to have the result shown on enter: =SUM('Start :Spacer'!A1)
Add any number of new Worksheets, enter some numbers into A1 of any Worksheet and it will be included in the SUM. Move the Worksheets order around, Delete sheets etc and the SUM function still includes all Worksheets.

If you have concerns that a user may unhide/delete/move the Worksheets "Start & "Spacer", go to Tools>Protection>Protect Workbook (ensure "Structure" is checked), supply a password (optional) and click OK.

From http://www.ozgrid.com/News/excel-validation-tips.htm

However, I cant get the code to work when following the guide. I tryed replacing the : with a ; so that the result is:
=SUM('Start;Spacer'!A1)

However this just open the 'look in explorer' as I was to open a new file.

Can you get it to work, and how?

Thanks

You will need to post your sample file... ie

=SUM('Start:Spacer'!A1)

should work ...

So... what is the result you get with the above ? #REF! or something else ?

If #REF! do you have sheets called Start & Spacer in your file ?