If you've upgraded your Photoshop you may be able to move the Greeting Card actions from one version to another. The keyword is "may".
If you moved from CS3 to CS4 you should have no problems. Adobe made some changes in earlier versions of Photoshop that rendered many actions obsolete so you will have problems if you convert from Version 7 or CS to any newer version. In such a case you will need to purchase the latest version of Greeting Card Designer.
How to Move Your Greeting Card Actions
Locate the actions file Greeting Card Designer V4.atn. The exact location for this file depends upon your operating system and Photoshop version so use Spotlight on the Mac or any file finder in Windows.
Can't find the file? No problem. Open Photoshop CS3 and open the Actions Palette. Highlight the Greeting Card Designer V4 action set. From the Actions Palette drop-down menu select Save Actions... The file name will default to the name of the Action set so you just need to save them to a location you'll remember such as the desktop.
Now open Photoshop CS4. Open the Actions Palette and from the drop-down menu click on Load Actions... Look for the file you found above.
You should now have the actions loaded in CS4 so the only thing left to do is to make a backup copy of the Greeting Card Designer V4.atn file.
Special Note for GCD V4.5. The instructions above assume you are upgrading Photoshop on the same computer. If you have a version of Greeting Card Designer that uses the Signature.psd file to add your branding to the back of a card AND you are moving to a new computer system, you will also need to move the Signature file. See the Signature Block Overview page for more information on the Signature file.