Hi jrace, thank you so much for your reply I really appreciate:)
Please could you tell me where do I put aosbrowserpluginlocalstoragescope.com to exclude it from cleaning?
Thanks again.
happy avast user 
1. Firefox: open a web page to get the cookie, go to "Settings" (see picture "Firefox"), uncheck cookies if checked!
2. CCleaner: open "Settings" (see picture "CCleaner") mark the quested cookie and transfer it with the corresponding arrow in the middle from the left to the right side.
3. Internet Explorer: I am not familiar with that one but there must be also some kind of security setting where you can prevent cookie cleaning when closing the browser.
Good Luck!