diff --git a/racket/collects/setup/main.rkt b/racket/collects/setup/main.rkt
index 08158b7567..ab099ea2d2 100644
--- a/racket/collects/setup/main.rkt
+++ b/racket/collects/setup/main.rkt
@@ -74,8 +74,9 @@
       (member flag-name flags)))
 
   (define-values (print-bootstrapping)
-    (lambda ()
-      (fprintf (current-output-port) "~a: bootstrapping from source...\n" short-name)))
+    (lambda (why)
+      (fprintf (current-output-port) "~a: bootstrapping from source...\n  (~a)\n"
+               short-name why)))
 
   (define-values (main-collects-relative->path)
     (let ([main-collects #f])
@@ -97,7 +98,7 @@
       (when (or (on? "--clean")
                 (on? "-c"))
 	(use-compiled-file-paths null)
-	(print-bootstrapping))
+	(print-bootstrapping "command-line --clean or -c"))
   
       ;; Load the cm instance to be installed while loading Setup PLT.
       ;; This has to be dynamic, so we get a chance to turn off compiled
@@ -117,21 +118,22 @@
 		    ;;  tree, and there's always --clean to turn this
 		    ;;  off. If an .so file is used, we give up using
 		    ;;  compiled files.
-		    (let loop ([skip-zo? (null? (use-compiled-file-paths))])
-		      (when skip-zo?
-			(print-bootstrapping))
+		    (let loop ([skip-zo/reason (and (null? (use-compiled-file-paths))
+                                                    "empty use-compiled-file-paths")])
+		      (when skip-zo/reason
+			(print-bootstrapping skip-zo/reason))
 		      ((call-with-escape-continuation
                         (lambda (escape)
 			 ;; Create a new namespace, and also install load handlers
 			 ;;  to check file dates, if necessary.
 			 (parameterize ([current-namespace (make-kernel-namespace)]
 					[use-compiled-file-paths 
-					 (if skip-zo?
+					 (if skip-zo/reason
 					     null
 					     (use-compiled-file-paths))]
 					[current-load 
 					 (let ([orig-load (current-load)])
-					   (if skip-zo?
+					   (if skip-zo/reason
 					       orig-load
 					       (lambda (path modname)
 						 (if (regexp-match? #rx#"[.]zo$" (path->bytes path))
@@ -159,24 +161,26 @@
 						     ;; Not a .zo! Don't use .zo files at all...
 						     (escape (lambda ()
 							       ;; Try again without .zo
-							       (loop #t)))))))]
+							       (loop (format "loading non-.zo: ~a" path))))))))]
 					[current-load-extension 
-					 (if skip-zo?
+					 (if skip-zo/reason
 					     (current-load-extension)
 					     (lambda (path modname)
 					       (escape (lambda ()
 							 ;; Try again without .zo
-							 (loop #t)))))])
+							 (loop "loading an extension")))))])
 		           ;; Other things could go wrong, such as a version mismatch.
 		           ;; If something goes wrong, of course, give up on .zo files.
                            (parameterize ([uncaught-exception-handler
                                            (lambda (exn)
                                              (when (exn:break? exn) (exit 1))
-                                             (if skip-zo?
+                                             (if skip-zo/reason
                                                  (escape
                                                   (lambda () (raise exn)))
                                                  (escape
-                                                  (lambda () (loop #t)))))])
+                                                  (lambda () (loop (if (exn:fail? exn)
+                                                                       (regexp-replace* #rx"\n" (exn-message exn) "\n  ")
+                                                                       (format "uncaught exn: ~s" exn)))))))])
 			     ;; Here's the main dynamic load of "cm.rkt":
 			     (let ([mk
 				    (dynamic-require 'compiler/cm