Quoted from the keclone FAQ:

"i changed my system and now keyclone says 'LICENSE EXPIRED'

if you change your hardware, re-install your OS, or get a new machine, odds are good that your keyclone system-id will change. when that happens, your keyclone will pop-up as expired. this is due to the new system-id not being activated.

DON'T PANIC your license is still valid, and always will be... it's just not associated with the new system-id. to fix the situation, please drop me an email (or PM on the forums) containing your email address, old system-id and the new system-id. once i have that information, i will effect the transfer as soon as possible."

Don't know if he wants his email address stated here so I will just link you to the FAQ that contains his email address in the question immediately after the one quoted above:

https://solidice.com/keyclone/faq.html#kc_faq_19