That error message that you are seeing means that the Device ID does not match the device it is on. This can happen in some cases after a hard reset and can also happen when you've replaced your device and restored everything from the old device. If you restored the device certificate file Pocket Tunes uses to identify the device, that certificate refers to the previous device which of course does not match the new device.

What you need to do is:

1) Delete any tracks you've already transferred from online stores or libraries. Otherwise you will not be able to re-license the tracks. 

2) Open Pocket Tunes, go to the Tools menu and select 'Clear Licenses'. Pocket Tunes will ask you to confirm you want to clear the licenses, answer 'Yes'.

3) Then delete this file 'pTunes_DevCert.pdb'. It is in the internal (or main) memory of your Palm device. You can use the 'Delete' function found in the menu of the 'Applications' program of your device to delete it. It will appear there  as 'pTunes DevCert'.

Then try another transfer of your tracks.

Please contact NormSoft Support if this does not resolve the issue, http://www.pocket-tunes.com/scripts/support.php