Some applications require that you have the latest service Pack for Windows Vista installed to find out what Service Pack you have on your computer please do the following:

1.        Open Control Panel  (Press  and select Control Panel)

2.        Click System and Maintenance (If you can’t see this then you need to click Control Panel Home on the left hand bar)

3.        Click Find which version of Windows you are using

4.        Click Show More Details (Top right hand corner)

The latest service pack for Windows Vista can be found here http://www.update.microsoft.com/microsoftupdate/v6/vistadefault.aspx?ln=en-us .
When you click this link the Windows Update dialog box will open on your computer.

1. Click View Available Updates

2. In the Windows Vista section ensure Service Pack 1 is selected and click Install.  

If the update is not offered through windows update then you can use the multi computer download below.

If you need to update more than one computer then you can download the service pack in a single file from here http://www.microsoft.com/downloads/details.aspx?FamilyID=b0c7136d-5ebb-413b-89c9-cb3d06d12674&DisplayLang=en