I've also done it, but it gives me still the same: checking for updates on pc...
SOLVED: Continued
Hello POMOOC,
Did you try the fix that worked for others? Specifically, do not use the Windows Update utility (either manually or automatically) until afteryou download and install this particular patch directly from the Microsoft website. Yes, you'll see "checking for updates" while it gets ready to install the patch, but it's only doing that for this specific update - not all updates.
Click the download link in Microsoft Security Bulletin MS16-039 that corresponds to the version of Windows that you are running. In the detailed list on this page, you'll notice that 3145739 will replace 3139852 from March 2016.
You might want to search your system for "Installed Updates" (not Update History) and see if KB3139852 exists. Clearly that's a problem according to the Microsoft Bulletin referenced above.
Good luck.
Joel