Hi,
Could you please let me know the installation order?
Did you install Productstream 2008 first and then Inventor 2008?
In that case, you may go to Add/Remove programs in control panel, Select Productstream 2008 > Click "Change" button.
In the installation Wizard, choose "Add/Remove Features" and enable "Inventor Vault Add-in" checkbox and complete the installation.
Then, you can launch Inventor application and check whether InventorVault Add-in is available.
Regards,
Madhan
Madhanagopal Thiruvenkatachalam
Principal Engineer
Engineering Escalation Team
Autodesk, Inc.