The licence is invalid or has expired. Without a valid licence, you can not use the avast! application anymore.
but there is know there for me to enter it and when i click “change license” everything clothes out…and ideas on what i can do?
http://www.avast.com/eng/faq-registration-license.html#idt_1442
Which one do you have? Linux, Unix, or Mac?
i have a mac
Alrighty, did you purchase a license yet, or were you using the 60-day trial, and it just ran out?
This thread may help you out. http://forum.avast.com/index.php?topic=34084.msg323510#msg323510
im using the free trial…so im not sure. i put a key in when i first got it in August. also that thread didn’t help 
Ok, from what you’re telling me, I’m assuming that you were using the 60 day trial, it ran out, and now it’s expired.
From this point, if you wish to continue using avast, you’ll have to purchase a license key.
Go here for purchase information: http://www.avast.com/eng/buy-avast-antivirus-mac-edition.html
Then, you’ll get an email with a license file in it. You should save the file on your computer, then select License from the avast menu and then navigate to the license file on your hard disk.
Hallo,
there’s no key, but license file, on Mac. After choosing “change license”, a file requester should pop up, allowing you to point to the license file. No “clothes off”, at least AFAIK :).
regards,
pc
Sorry for my incorrect terminology. This should make sense still though:
Then, you’ll get an email with a license file in it. You should save the file on your computer, then select License from the avast menu and then navigate to the license file on your hard disk.
I have an imac and I have this same problem, but I am pretty sure it was a twelve month free version that I installed and then added the license key. Yet it is about 2 months and saying it needs a new license.
Even though your symptoms are similar to the original poster, please start your own thread. Helping two people in the same thread can be very confusing to everyone.
As for a response to your question though, there is no “12 month” free trial, the trials are only 60 days (or 30?). After that period of time, a license must be purchased if you decide to keep the product, which is why at 2 months, it’s asking for a license.
As has been said, Avast for Mac is not free. You can use the software for 60 Days as a trial version after that time you must purchase a license. You can purchase from the avast website or by contacting your local reseller.