Tekkengamewin64shippingexe ((full)) Link
Because tekkengamewin64shipping.exe manages network connectivity for online matches, some overzealous antivirus software (especially Windows Defender at times) flags it as a "network threat." The executable is removed, and Steam complains that the "executable is missing."
If you are experiencing issues with this executable, follow these steps: tekkengamewin64shippingexe