Anyx64 version of the C++ Redistributable between 2008 - 2012 will work with 64 bit installer versions of Vegas through Pro 14, maybe later. The no-brainer clue, of course, is that x86 C++ Redistributables will not allow system registration of files destined for installation in the "Program Files x86" folder.
As proof, I successfully installed Pro 14 and MSP 13 on a new Win 10 box, but only after installing Pro 8.0c, of which the installer downloaded 2008 x64 in addition to 2008 x86, because it was the first Vegas to include a 64 bit .exe (which fell from grace rather quickly). 2012 C++ is not on this machine, and the only new one is 2008 x64, which allowed MSP 13 and Pro 14 to install after multiple previous fails. Go figure.
Here is the Microsoft 2012 Redistributable download:
For the record ... got the ERROR 2147163964 during install of VP17 on my new Dell laptop XPS 15 7590 running Windows 10 .. The error was that C:\Program Files (x86)\Sony\Shared Plug-Ins\Audio_x64\sfppack1_x64.dll would not register. The answer was that my new laptop did not have the necessary C++ 2008 Redistributable Package (x86) installed. Once that was installed, all went well.
Obviously Vegas needs this or up to the 2012 C++ Redistributable Package (x86) .. There is lots of bad advice regarding this error out there. First would be to be sure you have the needed C++ installed on your system.
Ok. With many thanks to all contr8butors to this thread with special shout out to Musicvid, I am confirming that Microsoft etc. downloads of Microsoft Visual C++ 2008 Redistributable Package (x86) and Microsoft Visual C++ 2008 Redistributable Package (x64) solve the Vegas Pro versions 14 and up install issue for ERROR 2147163964Shared Plug-Ins\Audio_x64\sfppack1_x64.dll
Musicvid's 2012 version didn't solve the problem for me. However, the 2008 version did. Links below. Download both, run and restart, then install your Vegas Pro. I just installed VP18 and it was fine. Cheers!!