I have started getting a popup supposedly from Microsoft Security Essentials (which I have installed and run regularly along with MBAM and Spybot) that states that MSE has detected a file that it doesn't recognize and wants me to send to them. The popup looks legitimate but I am very suspicious of it because I've never gotten anything like this before and the directory that it lists doesn't exist. I have not allowed MSE to send the files and I dismiss the popup. MSE doesn't have to be running a scan in order for the popup to appear.
I am running Win7, Firefox v22.0. Here is a screenshot.