diff --git a/packages/antora-zip-contents-collector-extension/lib/index.js b/packages/antora-zip-contents-collector-extension/lib/index.js
index 4b8183f..3624bb6 100644
--- a/packages/antora-zip-contents-collector-extension/lib/index.js
+++ b/packages/antora-zip-contents-collector-extension/lib/index.js
@@ -195,7 +195,8 @@ function register ({ config, downloadLog }) {
             logger.trace(`Skipping local file URL ${url} due to missing worktree`)
             continue
           }
-          return ospath.join(worktree, ...url.split('/'))
+          const localFile = ospath.join(worktree, ...url.split('/'))
+          if (fs.existsSync(localFile)) return localFile
         }
       }
     }
diff --git a/packages/antora-zip-contents-collector-extension/test/zip-contents-collector-extension-test.js b/packages/antora-zip-contents-collector-extension/test/zip-contents-collector-extension-test.js
index 7cfbe1d..2d45086 100644
--- a/packages/antora-zip-contents-collector-extension/test/zip-contents-collector-extension-test.js
+++ b/packages/antora-zip-contents-collector-extension/test/zip-contents-collector-extension-test.js
@@ -591,7 +591,7 @@ describe('zip contents collector extension', () => {
 
     it('should use local zip and collect files', async () => {
       const extensionConfig = () => ({
-        locations: [{ url: 'build/${name}.zip' }, { url: 'build/${name}.zip' }],
+        locations: [{ url: 'build/missing/${name}.zip' }, { url: 'build/${name}.zip' }],
       })
       const componentConfig = { include: ['start-page'] }
       await runScenario({