CiD is Mesenger Plus! Optional sponsor. Since Plus! does not work on the new public version of Messenger 9 you should uninstall Plus! anyway, this prevents possible interferences. Please exit your internetbrowser too whilst you uninstall (can't remove what's in use). Now if you reinstall Plus! again once we have a compatible version make sure "Install the sponsor" isn't checked (not checked by default) if you do not want these popups.
How to uninstall ad-ware/sponsor
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