Downgrade 2010 to 2009

My year subscription was about to run out on my Norton 2009, so I bought 2010 and just upgraded the subscription to another year. Using 2010 was great, but I'm having problems with the new SONAR thing. Everytime I open an executible file, it quarantines it and I have to manually go in and unquarantine it and make sure it doesn't quarantine that particualr file again. If I just turn SONAR off, it says my PC is at risk. Fixing the risk just turns SONAR back on again.  I just hate having to go in and manually fixing things since it's a hassle to me (I'm not very tech savy) and I would really like to have 2009 back.

 

So my question is, can I unistall 2010 and reinstall 2009 and still keep my year subscription? Is there anything that I have to follow or do I have to buy another subsciption when I reinstall 2009?

 

Thanks for your help!