diff --git a/.github/workflows/windows-cmake.yml b/.github/workflows/windows-cmake.yml
index 3d43b7e91..c0aeaa010 100644
--- a/.github/workflows/windows-cmake.yml
+++ b/.github/workflows/windows-cmake.yml
@@ -93,17 +93,23 @@ jobs:
           chmod +x "$RUNNER_TEMP/cxx-launcher.sh"
 
       - name: CMake configure
-        run: >
-          cmake -G Ninja -B Build-cmake -S .
-          "-DCMAKE_CXX_COMPILER_LAUNCHER=bash;$RUNNER_TEMP/cxx-launcher.sh"
-          -DCMAKE_POLICY_VERSION_MINIMUM=3.5
-          -DCMAKE_BUILD_TYPE=Release
-          -DRS_RNPLIB=ON -DRS_JSON_API=ON -DRS_WEBUI=OFF
-          -DRS_SQLCIPHER=ON -DRS_BITDHT=ON
-          -DRS_BRODCAST_DISCOVERY=ON -DRS_MINIUPNPC=ON
-          -DRS_FORUM_DEEP_INDEX=OFF
-          -DCMAKE_C_FLAGS="-include string.h -include stdint.h"
-          -DCMAKE_CXX_FLAGS="-include cstring -include cstdint -Wno-template-body"
+        run: |
+          # Plain "bash" would be resolved by CreateProcess to Windows' own
+          # C:\Windows\System32\bash.exe -- the WSL stub, which answers
+          # "Windows Subsystem for Linux has no installed distributions".
+          # Name the MSYS2 one, in a path CMake and ninja can both use.
+          BASH_EXE="$(cygpath -m "$(command -v bash)")"
+          LAUNCHER="$(cygpath -m "$RUNNER_TEMP/cxx-launcher.sh")"
+          cmake -G Ninja -B Build-cmake -S . \
+            "-DCMAKE_CXX_COMPILER_LAUNCHER=$BASH_EXE;$LAUNCHER" \
+            -DCMAKE_POLICY_VERSION_MINIMUM=3.5 \
+            -DCMAKE_BUILD_TYPE=Release \
+            -DRS_RNPLIB=ON -DRS_JSON_API=ON -DRS_WEBUI=OFF \
+            -DRS_SQLCIPHER=ON -DRS_BITDHT=ON \
+            -DRS_BRODCAST_DISCOVERY=ON -DRS_MINIUPNPC=ON \
+            -DRS_FORUM_DEEP_INDEX=OFF \
+            -DCMAKE_C_FLAGS="-include string.h -include stdint.h" \
+            -DCMAKE_CXX_FLAGS="-include cstring -include cstdint -Wno-template-body"
 
       - name: CMake build
         run: cmake --build Build-cmake -j3