Jock1e suggestion of using CCleaner Click Here is a good one and you only need the free version. It does remove many temporary files but this being a n exe file it may not do so. However as this pop up occurs on every boot up it is probably a Start Up file and if you scroll down to Tools on CCleaner you will see a start up Tab, click on that and see if you can locate the pop up file and if so Disable it. That won't delete the file but it will stop it from appearing on boot up.
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