What Virus software are you using? And is it blocking installation or preventing ProSeries from running? 

This happens occasionally.  The ProSeries application comes with dozens of third party libraries and processes it uses to do stuff, like print to PDF or display web pages. In this case CefSharp is a a desktop component we include in our 32bit installation directory. It is basically a small version of Chromium, the technology from Google that powers Chrome & Edge. CefSharp itself is a bunch of different files, one of which is that "Cefsharp.BrowserSubProcess.exe".   I think to fix this you should be able to open up your anti-virus software and grant an exception to the CefSharp.Browser.SubProcess.exe file in our ProSeries Installation Directory (in the 32Bit directory). But, to fix it for everyone, we'll probably need to contact the Anti-Virus vendor and get them to whitelist us / the version of CefSharp we're using.