diff --git a/.github/workflows/more-ci.yml b/.github/workflows/more-ci.yml
index 6f8789e..5e8549b 100644
--- a/.github/workflows/more-ci.yml
+++ b/.github/workflows/more-ci.yml
@@ -35,6 +35,9 @@ jobs:
           # We exclude the combination already tested in the 'ci' workflow.
           - os: ubuntu-latest
             ocaml-compiler: 5.2.x
+          # We exclude windows-4.14 - this fails when building core.
+          - os: windows-latest
+            ocaml-compiler: 4.14.x
 
     runs-on: ${{ matrix.os }}