winapiwinhttppacautoproxy

What's the difference between resolving WPAD in process and out of process?

In the WinHTTP autoproxy API, the WINHTTP_AUTOPROXY_OPTIONS will accept flags for WINHTTP_AUTOPROXY_RUN_INPROCESS and WINHTTP_AUTOPROXY_RUN_OUTPROCESS_ONLY. What's the difference between these two flags and when would you use them?

Solution

  • Figured this out. The out-of-process approach uses the WinInet service, which is deemed more secure. While MSDN doesn't say so explicitly, this is presumably because the in-proc option means the PAC's execution shares the same app context.