Avast update problem

When I try to update my avast i become a strange error:
The license key for this product is invalid or expired. License is valid until: Cz, 1.01.1970 Current date: N, 23.09.2007 :o

Cann somebody explain this??

NOTICE: I have buyed this in local computer store (it’s liquided now)

You can’t buy avast in a local computer store unles you are saying you bought the computer and it had avast installed on it ?

The date is clearly expired.
What version of avast do you have Home or Pro, check the about avast (right click the avast ‘a’ icon), example, Home version 4.7.1043 (the latest version number) ?

Can you post a screenshot of your About box, with the Registration Key branch expanded?

The key used are currently generated by a keygen thats all i can tell you…

All the key generated by the Avast keygen cz core after the new program releases are showing the 1970 releated year…

tq