You need to copy the Keys from your 1st computer to the other ones.

 

Transfer the keyrings. To do this, copy the keyring files (both pubring.pkrand secring.skr) from the old computer to diskette or other removable media, and then copy them to the new computer. The default location for the keyring files is

C:\\Documents and Settings\\\\My Documents\\PGP\\

 

If PGP Desktop has never been installed on the new computer, create this folder

first before copying the keyring files to the computer

 

Now you can install the program.

 

During the installation process, do the following:

During the PGP Desktop setup wizard on the new computer select No, I have existing keyrings and specify the location where you copied the keyring files to on the new computer.

Use the same name, organization, and license number used when PGP Desktop was originally authorized.

 

 

If you already installed it thats ok.  Just exit PGP Desktop in the bottom right. and then copy the files over.  Next time you open PGP Desktop it will use the new key.