When using Windows 7's File Explorer to upload or open graphics files in other apps. Thumbnails are very handy in seeing at a glance that do we have the right picture. Windows 7 Initially supported PNG, JPG, and even PDF thumbs are supported, but not PSD.
We need to rely on a third party solution. A programmer from Adobe has answered that Microsoft has the PSD documentation and this implies that the ball is in their court. I hope a Microsoft tech can pass this concern on or give me a reason why it can't happen at least in Windows 7.
PSD is as common as PDF and it has been around as long. The reason psicon.dll was dropped was over "file locking" issues with Windows.
Apple has been able to add support for PSDs in Quick Look without relying on Adobe, and MSFT has the PSD format documentation. That's not to say Adobe shouldn't step up, too. I guess Microsoft just haven't been able to find time to fix this issue during the release of Windows 7.
In the latest versions of Adobe Photoshop with the inclusion of Adobe Bridge the thumbnail view of PSD files within the windows explorer is no more present, This can be really difficult if you intent to see preview of the file you need to open the Adobe Bridge in order to view the preview, which consumes a lot of RAM.
PSD thumbnails be displayed in Windows 7 Service Pack 1. I guess that Microsoft has answered this issue in their Windows 7 Service Pack 1 Release as I can view the thumbnails of PSD Files in Windows 7 Ultimate -Service Pack 1. If you are using Windows 7, and it is time to update to Windows 7 Service Pack 1.
If you are not interested to install Windows 7 Service Pack 1, here is an another way to restore the thumbnail view for the PSD files within explorer.
The PSD thumbnail view is not included by design in the latest version of Photoshop. To restore this feature follow these steps:
2. Place the DLL in C:\Program Files\Common Files\Adobe\Shell\
3. Thumbnail previews of PSD files are now back