spreadsheet on form disappears

hI newbie here
I've created a form which has the microsoft office spreadsheet control on it. All the code works fine ad dandy and when i run the workbook containing the forms on my home pc it works fine too.
However, recently Ive tried to distribute the file to a couple of other pc's and when the form is activated the spreadsheet within it is missing. I've tried using version 11 and version 10 of the spreadsheet on the form and tried a number of versions of excel 2003 , 2007 but it still fails to appear.
The initial form was created using excel 2003 but im at a loss to understand why it keep failing to appear
I'm assuming i must have activated something on my home and work pc that i havent on the others. Ive got activex running on all the other pc's as i thought this may be the issue but isnt.
The only thing I can determine on one of the pc is that im using windows 2000 and they are using vista.
can anyone help ? thank you

thansk roy
ok

this is the bit i dont get cause when i open the form on the other pc and look in additional controls I can see microsoft office spreadsheet 10 and 11 there in the list just unticked.

I tick them

and then try and reload and still the spreadsheet on the form doesnt appear.

Is this the correct way of loading the additional control, I cant see it is as it doesnt seem to work, or do i have to declare something in the code itself to get it to load.

All the other controls on the form appear there fine, including the calender one which again is an addtional control