I have MSBuild and FxCop installed on Jenkins Master (in fact only have a master so far), so the .exe-files are present.
In the general configuration of MSBuild Plugin you have to specify the path to the MSBuild.exe.

• If you specify just the path, no warning is shown (as the path is present on the Jenkins Master), but the build fails (as MSBuild.exe is not appended to the path).
• If you specify the .exe itself, a warning is shown (see attached screenshot), even though the file is present. The build succeeds.

The same goes for the FxCopCmd.exe.

Expected behaviour: As it would influence present installtions otherwise, I suggest to change the label to "Full path to MSBuild.exe" (and ...FxCopCmd.exe) and let the warning check for the full path instead for a directory.