You need to update MBA-M and run a Full Scan with it. Do nothing else while it's running, close each and every browser. If it finds something, remove it.
Come back here with the log.
The longer you wait, the worse it will get. Do you use Incredimail? With smileys and such? I don't see it installed but your mail sure does contain those, take a look at my print screen...plus your mail is LOADED with ads for Inbox mail.

Where did you get the HiJackThis???? It was after you said you installed it that the ads began coming in the mails and the smilies began showing up.
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