diff --git a/collects/framework/private/frame.ss b/collects/framework/private/frame.ss
index 6e081a7411..3ee36437ac 100644
--- a/collects/framework/private/frame.ss
+++ b/collects/framework/private/frame.ss
@@ -1018,8 +1018,9 @@
       (define/override (editing-this-file? filename)
         (let ([path-equal?
                (λ (x y)
-                 (equal? (normal-case-path (normalize-path x))
-                         (normal-case-path (normalize-path y))))])
+                 (with-handlers ((exn:fail:filesystem? (λ (x) #f)))
+                   (equal? (normal-case-path (normalize-path x))
+                           (normal-case-path (normalize-path y)))))])
           (let ([this-fn (get-filename)])
             (and this-fn
                  (path-equal? filename (get-filename))))))