In the moment you open a license file, it leaves traces on the PC. Never use a license file twice for testing.
Every time you want to make a new test on the same machine, you have to create a new license file - Icon . Only a new license file guarantees to have the same situation like a user would have, after he installed your software.
Never deliver a file which was used for testing! Always create a new one to use in the installation package.
Page url: http://www.helpserver.biz/onlinehelp/lp/easygo/2.7/help2000/index.html?license_file___testing.htm