disapperaing from inbox

I've developed an issue recently. The last few days my inbox will show as one or two unread emails; however, when I try to open them, they're not there and seem to disappear. I've tried checking every folder. They're not there. I have my spam shut off and my anti-virus set to not scan my email just to make sure this type of thing didn't happen. If I go to the website to check for the email, it's no longer there either. Since I never get a chance to read these emails, I'm unsure what they are regarding. My guess is they're bouncebacks (unable to be delivered, out of office, etc); however, I'm not sure. Any ideas on where to look for them or how to stop this from happening?

I'm using Outlook2010 and have the spam filter shut off completely on Outlook, aol, and my anti-virus software.