diff -u b/includes/bootstrap.inc b/includes/bootstrap.inc
--- b/includes/bootstrap.inc
+++ b/includes/bootstrap.inc
@@ -990,9 +990,9 @@
 
   if (isset($files[$type][$name])) {
     // The requested file exists.
-    // Check if the file had previously been marked as missing.
-    if (isset($missing[$type][$name]) && $missing[$type][$name] === TRUE) {
-      // Previously missing file has reappeared.
+    // Check if the file had previously been marked as missing or moved.
+    if (isset($missing[$type][$name]) && ($missing[$type][$name] === TRUE || (is_string($missing[$type][$name]) && $missing[$type][$name] != $files[$type][$name]))) {
+      // Previously missing/moved file has reappeared.
       $missing[$type][$name] = NULL;
       $missing['#write_cache'] = TRUE;
     }