diff --git a/.github/workflows/R-CMD-check.yaml b/.github/workflows/R-CMD-check.yaml
index 79f20e9..f8c13fc 100644
--- a/.github/workflows/R-CMD-check.yaml
+++ b/.github/workflows/R-CMD-check.yaml
@@ -54,8 +54,8 @@ jobs:
         if: runner.os == 'Windows'
         run: |
           pacman -Syu mingw-w64-x86_64-fftw mingw-w64-x86_64-openmp --noconfirm
-          export CPPFLAGS="-I/mingw64/lib ${CPPFLAGS}"
-          export LDFLAGS="-L/mingw64/bin $LDFLAGS"
+          set CPPFLAGS=-I/mingw64/lib %CPPFLAGS%
+          set LDFLAGS=-L/mingw64/bin %LDFLAGS%
 
       - uses: r-lib/actions/setup-r-dependencies@v2
         with: