Just in the last few days I'm getting pop unders if that's the correct term. Haven't had those for what seems like years. Most are those "lower my utilities" that I remember getting long ago. I don't know where to go to see if something has changed that is now allowing them.
We'll need more info. Is this using IE9 listed in your specs? Happens randomly, or at startup, on certain sites, etc? Happens on other browsers as well? Try running AdwCleaner and see if it can find the culprit.
AdwCleaner Download
Choose the Download Now @BleepingComputer link
How To Use AdwCleaner [Manual]
Report back with the log file if you are unsure what to delete. A Guy
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