This is my first post and wasn't sure if this was the right forum. If it is not, I
I think the feature was introduced in Jelly Bean (maybe it was ICS), try long pressing on the notification, that should pop up an "App Info" button you can press which will tell you what app created that notification (and conveniently you can disabled notifications and uninstall it from there).
I'm adding a screenshot with the problem in here. please help, its driving me crazy.
Go in Settings | Apps | All | and search the app Downloads, stop the app's running and clear its Data and Cache ... voila
I will move this to your device forum for more help and support.
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