- error MSB4019: The imported project "C:\Program Files (x86)\MSBuild\Microsoft\Portable\v4.0\Microsoft.Portable.CSharp.targets" was not found. Confirm that the path in the <Import> declaration is correct, and that the file exists on disk.
However when attempting to install I got a great message saying I needed VS2010 and SP1 installed, obviously for a build server this wasn't going to happen. After a bit of digging on MSDN I found that the installer actually has a switch that when used just installs the targets for MSBuild.
To install the Portable Class Library Tools on a build machine without installing Visual Studio 2010, save the download file (PortableLibraryTools.exe) on your computer, and run the installation program from a Command Prompt window. Include the /buildmachine switch on the command line.
Simply run the installer with the /BuildMachine switch and everything installs hunky dory.
To my great relief the build server started building again and things went back to normal.