diff --git a/win/build-deps.cmd b/win/build-deps.cmd
index 96a5150bf0..55f109ff56 100644
--- a/win/build-deps.cmd
+++ b/win/build-deps.cmd
@@ -181,8 +181,8 @@ echo.
 
 cd "%DEPS_DIR%"
 
-:: VERSIONS
-set OCCT_VERSION=7.8.1
+:: VERSIONS
+set OCCT_VERSION=7.8.1
 IF DEFINED QT6_VERSION (
     echo Using overridden QT6_VERSION: '%QT6_VERSION%'
 ) else (
@@ -209,8 +209,8 @@ IF "%IFCOS_INSTALL_PYTHON%"=="TRUE" (
 :: Cache last used CMake generator and configurable dependency dirs for other scripts to use
 :: This is consolidated at the beginning of the script so that the script can be partially
 :: executed by jumping (using goto) to different labels.
-if defined GEN_SHORTHAND echo GEN_SHORTHAND=%GEN_SHORTHAND%>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
-echo QT6_VERSION=%QT6_VERSION%>>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
+if defined GEN_SHORTHAND echo GEN_SHORTHAND=%GEN_SHORTHAND%>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
+echo QT6_VERSION=%QT6_VERSION%>>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
 IF "%IFCOS_INSTALL_PYTHON%"=="TRUE" (
     echo PYTHONHOME=%PYTHONHOME%>>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
 )
@@ -342,10 +342,10 @@ popd
 
 :mpfr
 
-IF EXIST "%INSTALL_DIR%\mpfr" (
-    echo Found existing "%INSTALL_DIR%\mpfr", skipping
-    goto :Boost
-)
+IF EXIST "%INSTALL_DIR%\mpfr" (
+    echo Found existing "%INSTALL_DIR%\mpfr", skipping
+    goto :Boost
+)
 
 set DEPENDENCY_NAME=mpfr
 set DEPENDENCY_DIR=%DEPS_DIR%\mpfr
@@ -378,9 +378,9 @@ copy lib\%VS_PLATFORM%\%DEBUG_OR_RELEASE%\* "%INSTALL_DIR%\mpfr"
 IF NOT %ERRORLEVEL%==0 GOTO :Error
 popd
 
-:: Note all of the dependencies have appropriate label so that user can easily skip something if wanted
-:: by modifying this file and using goto.
-:Boost
+:: Note all of the dependencies have appropriate label so that user can easily skip something if wanted
+:: by modifying this file and using goto.
+:Boost
 :: DEPENDENCY_NAME is used for logging and DEPENDENCY_DIR for saving from some redundant typing
 set DEPENDENCY_NAME=Boost %BOOST_VERSION%
 set DEPENDENCY_DIR=%DEPS_DIR%\boost_%BOOST_VER%
@@ -741,7 +741,7 @@ IF NOT %ERRORLEVEL%==0 GOTO :Error
 call :MarkInstallation
 
 :qt6
-set DEPENDENCY_NAME=Qt6 %QT6_VERSION%
+set DEPENDENCY_NAME=qt6
 
 set QT6_MSVC_YEAR=%VS_VER%
 IF /I "%VS_TOOLSET%"=="v141" set QT6_MSVC_YEAR=2017
@@ -769,6 +769,10 @@ set DEPENDENCY_INSTALL_NAME=qt6-%QT6_VERSION%-%QT6_INSTALL_SUFFIX%
 set QT6_AQT_OUTPUT_DIR=%INSTALL_DIR%\%DEPENDENCY_INSTALL_NAME%
 set QT6_INSTALL_DIR=%QT6_AQT_OUTPUT_DIR%\%QT6_VERSION%\%QT6_INSTALL_SUFFIX%
 set QT_DIR=%QT6_INSTALL_DIR%
+set QT6_CONFIG_DLL=Qt6Core.dll
+IF /I "%BUILD_CFG%"=="Debug" (
+    set QT6_CONFIG_DLL=Qt6Cored.dll
+)
 set NEXT_DEPENDENCY_LABEL=Successful
 
 IF NOT "%IFCOS_INSTALL_QT6%"=="TRUE" (
@@ -782,8 +786,8 @@ echo QT_DIR=%QT_DIR%>>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
 call :CheckInstallation
 if %ERRORLEVEL%==200 GOTO %NEXT_DEPENDENCY_LABEL%
 
-IF EXIST "%QT6_INSTALL_DIR%\lib\cmake\Qt6\Qt6Config.cmake" (
-    echo Found existing "%QT6_INSTALL_DIR%", skipping
+IF EXIST "%QT6_INSTALL_DIR%\bin\%QT6_CONFIG_DLL%" (
+    echo Found existing "%QT6_INSTALL_DIR%" for %BUILD_CFG%, skipping
     call :MarkInstallation
     goto :Successful
 )
@@ -802,6 +806,11 @@ IF NOT EXIST "%QT6_INSTALL_DIR%\lib\cmake\Qt6\Qt6Config.cmake" (
     GOTO :Error
 )
 
+IF NOT EXIST "%QT6_INSTALL_DIR%\bin\%QT6_CONFIG_DLL%" (
+    call cecho.cmd 0 12 "Qt6 installation did not produce %BUILD_CFG% runtime %QT6_CONFIG_DLL% at %QT6_INSTALL_DIR%\bin."
+    GOTO :Error
+)
+
 call :MarkInstallation
 goto :Successful
 
diff --git a/win/utils/tools.ps1 b/win/utils/tools.ps1
index a36186c508..ad7f04de5d 100644
--- a/win/utils/tools.ps1
+++ b/win/utils/tools.ps1
@@ -56,6 +56,11 @@ function mark_based_on_artifacts {
             $artifact = "lib\rocksdb.lib"
         }
     }
+    elseif ($dependency_name -eq "qt6") {
+        # Qt has a nested install layout, so build-deps.cmd validates its
+        # Release/Debug artifacts before marking the installation.
+        return
+    }
     else {
         throw "Unexpected dependency name '$dependency_name'."
     }
@@ -104,6 +109,7 @@ function check_installation {
 # - OpenCASCADE: incompatible
 # - rocksdb: incompatible
 # - opencollada: incompatible
+# - Qt6: compatible when both Release and Debug artifacts are installed
 # - zstd: compatible
 
 function setup_build_cfg {