If this just started happening it may be related to a defect that causes this message to appear when you have an expiring license. Try opening PADS Router from the Desktop icon, if there is an expiring license situation it should allow the Router to start using this method. The other check would be if you are getting a license expiring message when you are starting PADS Layout. If you do get the license expiring notice you can download an updated license file from SupportNet by clicking on the Licenses link in the left hand nav bar.
Yes, I have an expiring license, and your solution to use the desktop icon works!