I have been running the free versions for over 12 months. A recent PC upgrade to Win10 has resulted in eClient repeatedly saying the license requires activation. I enter the long winded code which I have copied to a word processor and simply copy out to enter. This works but it is becoming irritating and if I can’t fix it I will stop using eClient.
Are you perhaps trying to use the same license code on multiple machines? The license is for only one machine. If you activate it on another, it will deactivate the original machine. So, if you go back and forth between machines, you will continually be reactivating. You can get a second free license by registering with a different email address.
If this is not the case, contact firstname.lastname@example.org and they will help.