Hi,
Windows Runtime (WinRT) is a platform application which supports the development of C+, C, Java, and other codes. You can update Universal C Runtime and other Windows Runtime by updating Windows 8.1 itself. To update Windows 8.1, kindly refer to this link. If you are encountering issues doing an automatic update on your PC, you can install the update manually. You can download the latest Windows 8.1 update here.
If you need further assistance, feel free to reach us out.
Regards.
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