In this scenario, the VBP console app (visbuildcmd.exe) will run on the web server, not the build machine (\\esbuild-vista), and VBP must be installed on the web server machine in order to run a build there.
If you instead want to initiate a build on the build machine from the web server machine, install
PsExec on the web server and launch the build on the build machine, something like this:
PsExec \\esbuild-vista "c:\program files\visbuildpro6\visbuildcmd" /b c:\path\to\trios.bld
Note that filenames must be absolute paths on the remote/target machine.