We are attempting to install an Outlook 2007 Visual Studio Tools for Office
(VSTO) Addin for a client.
The MSI file includes a custom action to set the necessary Caspol
permissions.

When they attempt to run the installer on a Vista machine (using an
administrator account) it fails with Error 2869.

Research on the internet has uncovered two suggested solutions. The first is
a workaround that involves running the MSI file from a command prompt using
msiexec i/ filename.msi as an administrator. This did not work.

The second solution was to alter the MSI file to set the custom actions
NoImpersonate flag. When I attempted this solution using ORCA to edit the MSI
file, the resulting file was corrupted and gave the error 2356 "Could not
locate cabinet in stream:"

Can anyone suggest an alternate solution to the problem of deploying this
addin?

Any advice would be appreciated.