When you attempt to launch Adobe After Effects, it crashes and displays the following error message:

<GPUManager> <2> Sniffer Result Code: 3

Solution: Update Windows 7 to Service Pack 1

After Effects requires Windows 7 Service Pack 1 (SP1). See Microsoft's website for instructions on how to apply the Service Pack 1 update. 

External link: Learn how to install Windows 7 Service Pack 1