my avast has been turned off

my avast has been turned off and i cant turn it back on. when i try it says i dont have an account. i have only used 3 months of my one year svc. what do i do

Please contact avast…!
http://www.avast.com/contacts
asyn

What do you mean by you don’t have an account, do you mean the license has expired/invalid, can you post a screen shot of the error message Or copy the full text of the message ?

What version of avast do you have installed avast 5.0 Pro or avast 5.0 AIS ?

Also, check your system time and date and run a full scanning. Some malware could try to make that things to the antivirus.