With the Vista consumer launch just days away, Microsoft has some tips on installing GP 9 on Vista. This is from Knowledge Base article 929908. I haven't played with GP on Vista so I can't verify this.
To run Microsoft Dynamics GP on a computer that is running Windows Vista, you have to:
• Turn off User Account Control (UAC) in Windows Vista before you install Microsoft Dynamics GP. To turn off UAC, follow these steps:
1. Click Start, click Settings, and then click Control Panel.
2.Under User Account and Family settings, click Add or…