diff --git a/.github/workflows/preview.yml b/.github/workflows/preview.yml
index 49f369153..edf7ea524 100644
--- a/.github/workflows/preview.yml
+++ b/.github/workflows/preview.yml
@@ -9,7 +9,11 @@ on:
       - closed
 
 permissions:
-  contents: write 
+  contents: write
+  pages: write
+  id-token: write
+  pull-requests: write
+
 
 concurrency: preview-${{ github.ref }}
 
@@ -38,9 +42,12 @@ jobs:
         jupyter-book build DISCOVER
 
     - name: Deploy PR Preview
+      # Only run on non-fork PRs to avoid permission errors 
+      if: ${{ github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name }}
       uses: rossjrw/pr-preview-action@v1
       with:
         source-dir: ./DISCOVER/_build/html/
         preview-branch: gh-pages
         umbrella-dir: pr-preview
         action: auto
+        token: ${{ secrets.PREVIEW_TOKEN || secrets.GITHUB_TOKEN }}