diff --git a/tools/internal_ci/helper_scripts/install_python38.ps1 b/tools/internal_ci/helper_scripts/install_python38.ps1
index 251eda0d76c..1c17dba3d66 100644
--- a/tools/internal_ci/helper_scripts/install_python38.ps1
+++ b/tools/internal_ci/helper_scripts/install_python38.ps1
@@ -4,6 +4,12 @@
 Set-StrictMode -Version 2
 $ErrorActionPreference = 'Stop'
 
+trap {
+    $ErrorActionPreference = "Continue"
+    Write-Error $_
+    exit 1
+}
+
 # Avoid "Could not create SSL/TLS secure channel"
 [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
 
@@ -19,7 +25,7 @@ function Install-Python {
 
     # Downloads installer
     Write-Host "Downloading the Python installer: $PythonInstallerUrl => $PythonInstallerPath"
-    Invoke-WebRequest -Uri $PythonInstallerUrl -OutFile $PythonInstallerPath
+    Invoke-WebRequest -Uri $PythonInstallerUrl -OutFile $PythonInstallerPath -MaximumRetryCount 3
 
     # Validates checksum
     $HashFromDownload = Get-FileHash -Path $PythonInstallerPath -Algorithm MD5
diff --git a/tools/internal_ci/helper_scripts/prepare_build_windows.bat b/tools/internal_ci/helper_scripts/prepare_build_windows.bat
index 6b39d85ee1d..cda034adc91 100644
--- a/tools/internal_ci/helper_scripts/prepare_build_windows.bat
+++ b/tools/internal_ci/helper_scripts/prepare_build_windows.bat
@@ -29,20 +29,23 @@ netsh interface ip add dnsservers "Local Area Connection 8" 8.8.8.8 index=2
 netsh interface ip add dnsservers "Local Area Connection 8" 8.8.4.4 index=3
 
 @rem Needed for big_query_utils
-python -m pip install google-api-python-client
+python -m pip install google-api-python-client || goto :error
 
 @rem C# prerequisites: Install dotnet SDK
-powershell -File src\csharp\install_dotnet_sdk.ps1
+powershell -File src\csharp\install_dotnet_sdk.ps1 || goto :error
 set PATH=%LOCALAPPDATA%\Microsoft\dotnet;%PATH%
 
 @rem Install Python 3.8.0
 @rem NOTE(lidiz): Python installer process may live longer than expected, and
 @rem has other side effects. It needs to be installed last to reduce impact.
-powershell -File tools\internal_ci\helper_scripts\install_python38.ps1
+powershell -File tools\internal_ci\helper_scripts\install_python38.ps1 || goto :error
 
 @rem Disable some unwanted dotnet options
 set NUGET_XMLDOC_MODE=skip
 set DOTNET_SKIP_FIRST_TIME_EXPERIENCE=true
 set DOTNET_CLI_TELEMETRY_OPTOUT=true
 
-git submodule update --init
+git submodule update --init || goto :error
+
+:error
+exit /b 1
diff --git a/tools/internal_ci/windows/grpc_build_artifacts.bat b/tools/internal_ci/windows/grpc_build_artifacts.bat
index be47fe670b6..473b6ee9822 100644
--- a/tools/internal_ci/windows/grpc_build_artifacts.bat
+++ b/tools/internal_ci/windows/grpc_build_artifacts.bat
@@ -19,7 +19,7 @@ choco install nasm -y --limit-output
 @rem enter repo root
 cd /d %~dp0\..\..\..
 
-call tools/internal_ci/helper_scripts/prepare_build_windows.bat
+call tools/internal_ci/helper_scripts/prepare_build_windows.bat || exit /b 1
 
 python tools/run_tests/task_runner.py -f artifact windows -j 4
 set RUNTESTS_EXITCODE=%errorlevel%
diff --git a/tools/internal_ci/windows/grpc_build_packages.bat b/tools/internal_ci/windows/grpc_build_packages.bat
index 19a805adfc2..a5bffb28c24 100644
--- a/tools/internal_ci/windows/grpc_build_packages.bat
+++ b/tools/internal_ci/windows/grpc_build_packages.bat
@@ -15,7 +15,7 @@
 @rem enter repo root
 cd /d %~dp0\..\..\..
 
-call tools/internal_ci/helper_scripts/prepare_build_windows.bat
+call tools/internal_ci/helper_scripts/prepare_build_windows.bat || exit /b 1
 
 @rem Move artifacts generated by the previous step in the build chain.
 powershell -Command "mv %KOKORO_GFILE_DIR%\github\grpc\artifacts input_artifacts"
diff --git a/tools/internal_ci/windows/grpc_distribtests.bat b/tools/internal_ci/windows/grpc_distribtests.bat
index 72d7076ec90..6b74972f359 100644
--- a/tools/internal_ci/windows/grpc_distribtests.bat
+++ b/tools/internal_ci/windows/grpc_distribtests.bat
@@ -15,7 +15,7 @@
 @rem enter repo root
 cd /d %~dp0\..\..\..
 
-call tools/internal_ci/helper_scripts/prepare_build_windows.bat
+call tools/internal_ci/helper_scripts/prepare_build_windows.bat || exit /b 1
 
 @rem Move packages generated by the previous step in the build chain.
 powershell -Command "mv %KOKORO_GFILE_DIR%\github\grpc\artifacts input_artifacts"
diff --git a/tools/internal_ci/windows/grpc_distribtests_standalone.bat b/tools/internal_ci/windows/grpc_distribtests_standalone.bat
index 80334674144..e0722dbf375 100644
--- a/tools/internal_ci/windows/grpc_distribtests_standalone.bat
+++ b/tools/internal_ci/windows/grpc_distribtests_standalone.bat
@@ -15,7 +15,7 @@
 @rem enter repo root
 cd /d %~dp0\..\..\..
 
-call tools/internal_ci/helper_scripts/prepare_build_windows.bat
+call tools/internal_ci/helper_scripts/prepare_build_windows.bat || exit /b 1
 
 python tools/run_tests/task_runner.py -f distribtest windows cpp -j 4
 set RUNTESTS_EXITCODE=%errorlevel%
diff --git a/tools/internal_ci/windows/grpc_run_tests_matrix.bat b/tools/internal_ci/windows/grpc_run_tests_matrix.bat
index c6277d0929e..01d1f811034 100644
--- a/tools/internal_ci/windows/grpc_run_tests_matrix.bat
+++ b/tools/internal_ci/windows/grpc_run_tests_matrix.bat
@@ -15,7 +15,7 @@
 @rem enter repo root
 cd /d %~dp0\..\..\..
 
-call tools/internal_ci/helper_scripts/prepare_build_windows.bat
+call tools/internal_ci/helper_scripts/prepare_build_windows.bat || exit /b 1
 
 python tools/run_tests/run_tests_matrix.py %RUN_TESTS_FLAGS%
 set RUNTESTS_EXITCODE=%errorlevel%