diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 56ec9b8e9c..0ae9b751ff 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -124,7 +124,7 @@ jobs:
     - uses: actions/cache@v1
       with:
         path: ${{ steps.composer-cache.outputs.dir }}
-        key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
+        key: ${{ runner.os }}-composer-${{ hashFiles('**\composer.lock') }}
         restore-keys: |
           ${{ runner.os }}-composer-