I have this error when configuring continuous integration in TFS server, but found the answer already. Maybe this will help others:
The imported project \"C:
Here's some PowerShell that fixed this issue for me by adding in the missing reference in MSBuild.exe.config on my Build server. Adjust paths to your VS version / targets path.
[xml]$msbuild_config = Get-Content -Path "C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\MSBuild\15.0\Bin\MSBuild.exe.config"
$webApplicationTarget = $msbuild_config.configuration.msbuildToolsets.toolset.property[0].Clone()
$webApplicationTarget.name = "MSWebApplicationTargets"
$webApplicationTarget.value = "C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\MSBuild\Microsoft\VisualStudio\v15.0\WebApplications"
$msbuild_config.configuration.msbuildToolsets.toolset.AppendChild($webApplicationTarget)
$msbuild_config.save("C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\MSBuild\15.0\Bin\MSBuild.exe.config")```