Thanks but this does not seem to achieve what I was asking. I want to be able to specify the expiration of a file, in say 6 months time and then say the activiation is only valid for 10 days. This prevents people distributing the activation key beyond the 10 day period the activation key is valid for. This is important for those of us who dont have the infrastructure to set up to use hardware-locked keys. I dont have a website and with 2000 active users of a file, i cant ask each of them to send me their system ID which means I have to manually hand out an activation key and the best way to prevent it spreading is to set an expiry on the activation key PLUS be able to set an expiry to the file itself as well. This was a great feature of xlscore. Let me know if you know how to do this here.