Hello,
Regarding the first issue, KB2538243 is not needed, which was released in 4/4/2012.Too old and has been replaced by new updates.
Regarding the second issue, check the Windows Installer service. Make sure the Windows Installer service is running. If it has stopped, start it. You can do this by following these steps:
Click Start in the taskbar and enter "services" in the search box to open.
Find "Windows Installer", and if it's "Stopped", right-click and select Startup.
Best Regards,
Hania Lian
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