You can also print the path of MSBuild.exe to the command line:

reg.exe query "HKLMSOFTWAREMicrosoftMSBuildToolsVersions4.0" /v MSBuildToolsPath

If you want to use MSBuild for .Net 4 then you can use the following PowerShell command to get the executable's path. If you want version 2.0 or 3.5 then just change the $dotNetVersion variable.

To run the executable you'll need to prepend the $msbuild variable with &. That will execute the variable.

# valid versions are [2.0, 3.5, 4.0]
$dotNetVersion = "4.0"
$regKey = "HKLM:softwareMicrosoftMSBuildToolsVersions$dotNetVersion"
$regProperty = "MSBuildToolsPath"

$msbuildExe = join-path -path (Get-ItemProperty $regKey).$regProperty -childpath "msbuild.exe"

&$msbuildExe

For cmd shell scripting in Windows 7, I use the following fragment in my batch file to find MSBuild.exe in the .NET Framework version 4. I assume version 4 is present, but don't assume the sub-version. This isn't totally general-purpose, but for quick scripts it may be helpful:

set msbuild.exe=
for /D %%D in (%SYSTEMROOT%Microsoft.NETFrameworkv4*) do set msbuild.exe=%%DMSBuild.exe

For my uses I'm exiting the batch file with an error if that didn't work:

if not defined msbuild.exe echo error: can't find MSBuild.exe & goto :eof
if not exist "%msbuild.exe%" echo error: %msbuild.exe%: not found & goto :eof

You can use this very trial PowerShell Command to get the MSBuildToolsPath from the registry.

PowerShell (from registry)

Resolve-Path HKLM:SOFTWAREMicrosoftMSBuildToolsVersions* | 
Get-ItemProperty -Name MSBuildToolsPath

Output

MSBuildToolsPath : C:Program Files (x86)MSBuild12.0binamd64
PSPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions12.0
PSParentPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions
PSChildName : 12.0
PSDrive : HKLM
PSProvider : Microsoft.PowerShell.CoreRegistry

MSBuildToolsPath : C:Program Files (x86)MSBuild14.0binamd64
PSPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions14.0
PSParentPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions
PSChildName : 14.0
PSDrive : HKLM
PSProvider : Microsoft.PowerShell.CoreRegistry

MSBuildToolsPath : C:WindowsMicrosoft.NETFramework64v2.0.50727
PSPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions2.0
PSParentPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions
PSChildName : 2.0
PSDrive : HKLM
PSProvider : Microsoft.PowerShell.CoreRegistry

MSBuildToolsPath : C:WindowsMicrosoft.NETFramework64v3.5
PSPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions3.5
PSParentPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions
PSChildName : 3.5
PSDrive : HKLM
PSProvider : Microsoft.PowerShell.CoreRegistry

MSBuildToolsPath : C:WindowsMicrosoft.NETFramework64v4.0.30319
PSPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions4.0
PSParentPath : Microsoft.PowerShell.CoreRegistry::HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions
PSChildName : 4.0
PSDrive : HKLM
PSProvider : Microsoft.PowerShell.CoreRegistry

or from the filesystem

PowerShell (from file system)

Resolve-Path "C:Program Files (x86)MSBuild*Binamd64MSBuild.exe"
Resolve-Path "C:Program Files (x86)MSBuild*BinMSBuild.exe"

Output

Path
----
C:Program Files (x86)MSBuild12.0Binamd64MSBuild.exe
C:Program Files (x86)MSBuild14.0Binamd64MSBuild.exe
C:Program Files (x86)MSBuild12.0BinMSBuild.exe
C:Program Files (x86)MSBuild14.0BinMSBuild.exe

@AllenSanborn has a great powershell version, but some folks have a requirement to use only batch scripts for builds.

This is an applied version of what @bono8106 answered.

msbuildpath.bat

@echo off

reg.exe query "HKLMSOFTWAREMicrosoftMSBuildToolsVersions14.0" /v MSBuildToolsPath > nul 2>&1
if ERRORLEVEL 1 goto MissingMSBuildRegistry

for /f "skip=2 tokens=2,*" %%A in ('reg.exe query "HKLMSOFTWAREMicrosoftMSBuildToolsVersions14.0" /v MSBuildToolsPath') do SET "MSBUILDDIR=%%B"

IF NOT EXIST "%MSBUILDDIR%" goto MissingMSBuildToolsPath
IF NOT EXIST "%MSBUILDDIR%msbuild.exe" goto MissingMSBuildExe

exit /b 0

goto:eof
::ERRORS
::---------------------
:MissingMSBuildRegistry
echo Cannot obtain path to MSBuild tools from registry
goto:eof
:MissingMSBuildToolsPath
echo The MSBuild tools path from the registry '%MSBUILDDIR%' does not exist
goto:eof
:MissingMSBuildExe
echo The MSBuild executable could not be found at '%MSBUILDDIR%'
goto:eof

build.bat

@echo off
call msbuildpath.bat
"%MSBUILDDIR%msbuild.exe" foo.csproj /p:Configuration=Release

For Visual Studio 2017 / MSBuild 15, Aziz Atif (the guy who wrote Elmah) wrote a batch script

build.cmd Release Foo.csproj

https://github.com/linqpadless/LinqPadless/blob/master/build.cmd

@echo off
setlocal
if "%PROCESSOR_ARCHITECTURE%"=="x86" set PROGRAMS=%ProgramFiles%
if defined ProgramFiles(x86) set PROGRAMS=%ProgramFiles(x86)%
for %%e in (Community Professional Enterprise) do (
 if exist "%PROGRAMS%Microsoft Visual Studio2017%%eMSBuild15.0BinMSBuild.exe" (
 set "MSBUILD=%PROGRAMS%Microsoft Visual Studio2017%%eMSBuild15.0BinMSBuild.exe"
 )
)
if exist "%MSBUILD%" goto :restore
set MSBUILD=
for %%i in (MSBuild.exe) do set MSBUILD=%%~dpnx$PATH:i
if not defined MSBUILD goto :nomsbuild
set MSBUILD_VERSION_MAJOR=
set MSBUILD_VERSION_MINOR=
for /f "delims=. tokens=1,2,3,4" %%m in ('msbuild /version /nologo') do (
 set MSBUILD_VERSION_MAJOR=%%m
 set MSBUILD_VERSION_MINOR=%%n
)
if not defined MSBUILD_VERSION_MAJOR goto :nomsbuild
if not defined MSBUILD_VERSION_MINOR goto :nomsbuild
if %MSBUILD_VERSION_MAJOR% lss 15 goto :nomsbuild
if %MSBUILD_VERSION_MINOR% lss 1 goto :nomsbuild
:restore
for %%i in (NuGet.exe) do set nuget=%%~dpnx$PATH:i
if "%nuget%"=="" (
 echo WARNING! NuGet executable not found in PATH so build may fail!
 echo For more on NuGet, see https://github.com/nuget/home
)
pushd "%~dp0"
nuget restore ^
 && call :build Debug %* ^
 && call :build Release %*
popd
goto :EOF

:build
setlocal
"%MSBUILD%" /p:Configuration=%1 /v:m %2 %3 %4 %5 %6 %7 %8 %9
goto :EOF

:nomsbuild
echo Microsoft Build version 15.1 (or later) does not appear to be
echo installed on this machine, which is required to build the solution.
exit /b 1

The Registry locations

HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions2.0
HKEY_LOCAL_MACHINESOFTWAREMicrosoftMSBuildToolsVersions3.5

give the location for the executable.

But if you need the location where to save the Task extensions, it's on

%ProgramFiles%MSBuild

This works for Visual Studio 2015 and 2017:

function Get-MSBuild-Path 

 $vs14key = "HKLM:SOFTWAREMicrosoftMSBuildToolsVersions14.0"
 $vs15key = "HKLM:SOFTWAREwow6432nodeMicrosoftVisualStudioSxSVS7"

 $msbuildPath = ""

 if (Test-Path $vs14key) 
 $key = Get-ItemProperty $vs14key
 $subkey = $key.MSBuildToolsPath
 if ($subkey) 
 $msbuildPath = Join-Path $subkey "msbuild.exe"
 
 

 if (Test-Path $vs15key) 
 $key = Get-ItemProperty $vs15key
 $subkey = $key."15.0"
 if ($subkey) 
 $msbuildPath = Join-Path $subkey "MSBuild15.0binamd64msbuild.exe"
 
 

 return $msbuildPath

easiest way might be to open PowerShell and enter

dir HKLM:SOFTWAREMicrosoftMSBuildToolsVersions

On Windows 2003 and later, type this command in cmd:

cmd> where MSBuild
Sample result: C:WindowsMicrosoft.NETFrameworkv4.0.30319MSBuild.exe

If nothing appears, it means that .NET framework is not included in the system PATH. The MSBuild should be in the .NET installation folder, along with .NET compilers (vbc.exe, csc.exe)

Starting with MSBuild 2017 (v15), MSBuild is now installed in a folder under each version of Visual Studio

Here are some examples of where MSBuild.exe is found on my machine:

C:windowsMicrosoft.NETFrameworkv2.0.50727MSBuild.exe (v2.0.50727.8745 32-bit)
C:windowsMicrosoft.NETFramework64v2.0.50727MSBuild.exe (v2.0.50727.8745 64-bit)
C:WindowsMicrosoft.NETFrameworkv3.5MSBuild.exe (v3.5.30729.8763 32-bit)
C:WindowsMicrosoft.NETFramework64v3.5MSBuild.exe (v3.5.30729.8763 64-bit)
C:WindowsMicrosoft.NETFrameworkv4.0.30319MSBuild.exe (v4.7.2053.0 32-bit)
C:WindowsMicrosoft.NETFramework64v4.0.30319MSBuild.exe (v4.7.2053.0 64-bit)
C:Program Files (x86)MSBuild12.0BinMSBuild.exe (v12.0.21005.1 32-bit)
C:Program Files (x86)MSBuild12.0Binamd64MSBuild.exe (v12.0.21005.1 64-bit)
C:Program Files (x86)MSBuild14.0BinMSBuild.exe (v14.0.25420.1 32-bit)
C:Program Files (x86)MSBuild14.0Binamd64MSBuild.exe (v14.0.25420.1 64-bit)
C:Program Files (x86)Microsoft Visual Studio2017BuildToolsMSBuild15.0BinMSBuild.exe (v15.1.1012+g251a9aec17 32-bit)
C:Program Files (x86)Microsoft Visual Studio2017BuildToolsMSBuild15.0Binamd64MSBuild.exe (v15.1.1012+g251a9aec17 64-bit)
C:Program Files (x86)Microsoft Visual Studio2017LicenceNameMSBuildBinMSBuild.exe (v15.1.1012.6693 32-bit)
C:Program Files (x86)Microsoft Visual Studio2017LicenceNameMSBuildBinamd64MSBuild.exe (v15.1.1012.6693 64-bit)

To retrieve path of msbuild 15 (Visual Studio 2017) with batch from registry w/o additional tools:

set regKey=HKLMSOFTWAREWOW6432NodeMicrosoftVisualStudioSxSVS7
set regValue=15.0
for /f "skip=2 tokens=3,*" %%A in ('reg.exe query %regKey% /v %regValue% 2^>nul') do (
 set vs17path=%%A %%B
)
set msbuild15path = %vs17path%MSBuild15.0BinMSBuild.exe

Better available tools:

• 
  vswhere: Locate Visual Studio 2017 and newer installations, see get msbuild15 path with batch (uses hardcoded path as my snippet above).


• 
  Visual Studio Setup PowerShell Module by using Microsoft.VisualStudio.Workload.MSBuildTools
  

As of Visual Studio 2017, the "correct" way to do this is by invoking %ProgramFiles(x86)%Microsoft Visual StudioInstallervswhere.exe and appending the hardcoded path MSBuild15.0BinMSBuild.exe to the output, as per Microsoft's official wiki article.

Yes, it's even worse than reading the Registry directly, which I didn't think was possible - but Microsoft finds a way.

An one-liner based on @dh_cgn's answer:

(Resolve-Path ([io.path]::combine($env:ProgramFiles(x86), 'Microsoft Visual Studio', '*', '*', 'MSBuild', '*' , 'bin' , 'msbuild.exe'))).Path

It selects all existing paths paths of eg. C:Program Files (x86)Microsoft Visual Studio**MSBuild*binmsbuild.exe.

The wildcards stars are:

• the year (2017)


• the visual studio edition (community, professional, enterprise)


• the tools version (15.0)

Be aware that this command is selecting the first path that matches the expression ordered by alphabet. To narrow it down just replace the wildcards with specific elements eg. the year or tools version.

For Visual Studio 2017 without knowing the exact edition you could use this in a batch script:

FOR /F "tokens=* USEBACKQ" %%F IN (`where /r "%PROGRAMFILES(x86)%Microsoft Visual 
Studio2017" msbuild.exe ^| findstr /v /i "amd64"`) DO (SET msbuildpath=%%F)

The findstr command is to ignore certain msbuild executables (in this example the amd64).

add vswhere branch for https://github.com/linqpadless/LinqPadless/blob/master/build.cmd, works fine in my computer, and the vswhere branch works on my mate's computer.
May be, the vswhere branch should move forward as the first check.

@echo off
setlocal
if "%PROCESSOR_ARCHITECTURE%"=="x86" set PROGRAMS=%ProgramFiles%
if defined ProgramFiles(x86) set PROGRAMS=%ProgramFiles(x86)%
for %%e in (Community Professional Enterprise) do (
 if exist "%PROGRAMS%Microsoft Visual Studio2017%%eMSBuild15.0BinMSBuild.exe" (
 set "MSBUILD=%PROGRAMS%Microsoft Visual Studio2017%%eMSBuild15.0BinMSBuild.exe"
 )
)
if exist "%MSBUILD%" goto :build

for /f "usebackq tokens=1* delims=: " %%i in (`"%ProgramFiles(x86)%Microsoft Visual StudioInstallervswhere.exe" -latest -requires Microsoft.Component.MSBuild`) do (
 if /i "%%i"=="installationPath" set InstallDir=%%j
)

if exist "%InstallDir%MSBuild15.0BinMSBuild.exe" (
 set "MSBUILD=%InstallDir%MSBuild15.0BinMSBuild.exe"
)
if exist "%MSBUILD%" goto :build
set MSBUILD=
for %%i in (MSBuild.exe) do set MSBUILD=%%~dpnx$PATH:i
if not defined MSBUILD goto :nomsbuild
set MSBUILD_VERSION_MAJOR=
set MSBUILD_VERSION_MINOR=
for /f "delims=. tokens=1,2,3,4" %%m in ('msbuild /version /nologo') do (
 set MSBUILD_VERSION_MAJOR=%%m
 set MSBUILD_VERSION_MINOR=%%n
)
echo %MSBUILD_VERSION_MAJOR% %MSBUILD_VERSION_MINOR%
if not defined MSBUILD_VERSION_MAJOR goto :nomsbuild
if not defined MSBUILD_VERSION_MINOR goto :nomsbuild
if %MSBUILD_VERSION_MAJOR% lss 15 goto :nomsbuild
if %MSBUILD_VERSION_MINOR% lss 1 goto :nomsbuild
:restore
for %%i in (NuGet.exe) do set nuget=%%~dpnx$PATH:i
if "%nuget%"=="" (
 echo WARNING! NuGet executable not found in PATH so build may fail!
 echo For more on NuGet, see https://github.com/nuget/home
)
pushd "%~dp0"
popd
goto :EOF

:build
setlocal
"%MSBUILD%" -restore -maxcpucount %1 /p:Configuration=%2 /v:m %3 %4 %5 %6 %7 %8 %9
goto :EOF

:nomsbuild
echo Microsoft Build version 15.1 (or later) does not appear to be
echo installed on this machine, which is required to build the solution.
exit /b 1

If you are adventurous you can also get the source code and latest release of MsBuild from GitHub now at https://github.com/Microsoft/msbuild/releases/

If You want to compile a Delphi project, look at "ERROR MSB4040 There is no target in the project" when using msbuild+Delphi2009

Correct answer there are said: "There is a batch file called rsvars.bat (search for it in the RAD Studio folder). Call that before calling MSBuild, and it will setup the necessary environment variables. Make sure the folders are correct in rsvars.bat if you have the compiler in a different location to the default."

This bat will not only update the PATH environment variable to proper .NET folder with proper MSBuild.exe version, but also registers other necessary variables.