diff --git a/collects/setup/setup-unit.ss b/collects/setup/setup-unit.ss
index 1a666b09f9..54884b70ca 100644
--- a/collects/setup/setup-unit.ss
+++ b/collects/setup/setup-unit.ss
@@ -887,7 +887,7 @@
   (when (make-info-domain) (make-info-domain-step))
   (when (make-docs)
     ;; Double-check that "setup/scribble" is present.
-    (unless (file-exists? (build-path (collection-path "setup") "scribble.ss"))
+    (when (file-exists? (build-path (collection-path "setup") "scribble.ss"))
       (make-docs-step)))
 
   (when (doc-pdf-dest) (doc-pdf-dest-step))