diff --git a/lib/zone.ts b/lib/zone.ts
index 2d9c2ebbc..9deae5ce7 100644
--- a/lib/zone.ts
+++ b/lib/zone.ts
@@ -609,19 +609,7 @@ type AmbientZoneDelegate = ZoneDelegate;
 
 const Zone: ZoneType = (function(global: any) {
   if (global['Zone']) {
-    let zoneAlreadyLoadedMessage: string = 'Zone already loaded.';
-    // try to findout the already loaded zone.js script file
-    // require the loaded zone.js version to be newer than 0.8.6
-    try {
-      const LoadedZone: any = global['Zone'];
-      const scriptFileName: string = LoadedZone['__zone_symbol__scriptFileName'];
-      if (scriptFileName) {
-        zoneAlreadyLoadedMessage =
-            'Zone already loaded. The loaded Zone.js script file seems to be ' + scriptFileName;
-      }
-    } catch (error) {
-    }
-    throw new Error(zoneAlreadyLoadedMessage);
+    throw new Error('Zone already loaded.');
   }
 
   const NO_ZONE = {name: 'NO ZONE'};
@@ -636,17 +624,12 @@ const Zone: ZoneType = (function(global: any) {
 
     static assertZonePatched() {
       if (global.Promise !== ZoneAwarePromise) {
-        // try to findout the already loaded zone.js script file
-        // require the loaded zone.js version to be newer than 0.8.6
-        const scriptFileName: string = (Zone as any)[__symbol__('scriptFileName')];
-        const scriptFileErrorMessage: string =
-            scriptFileName ? 'the loaded Zone.js script file seems to be ' + scriptFileName : '';
         throw new Error(
             'Zone.js has detected that ZoneAwarePromise `(window|global).Promise` ' +
             'has been overwritten.\n' +
             'Most likely cause is that a Promise polyfill has been loaded ' +
             'after Zone.js (Polyfilling Promise api is not necessary when zone.js is loaded. ' +
-            'If you must load one, do so before loading zone.js.)' + scriptFileErrorMessage);
+            'If you must load one, do so before loading zone.js.)');
       }
     }
 
@@ -1809,24 +1792,11 @@ const Zone: ZoneType = (function(global: any) {
                 // Chrome: at Zone.run (http://localhost:9876/base/build/lib/zone.js:100:24)
                 // FireFox: Zone.prototype.run@http://localhost:9876/base/build/lib/zone.js:101:24
                 // Safari: run@http://localhost:9876/base/build/lib/zone.js:101:24
-                let frameParts: string[] = frame.split('(');
-                let fnNamePart: string = frameParts[0];
-
-                let fnName: string = fnNamePart.split('@')[0];
+                let fnName: string = frame.split('(')[0].split('@')[0];
                 let frameType = FrameType.transition;
                 if (fnName.indexOf('ZoneAwareError') !== -1) {
                   zoneAwareFrame1 = frame;
                   zoneAwareFrame2 = frame.replace('Error.', '');
-
-                  // try to find the filename where zone.js live with
-                  let fileNamePart1: string = frameParts.length > 1 ? frameParts[1] : fnNamePart;
-                  let fileNameParts: string[] = fileNamePart1.split('@');
-                  let fileNamePart2: string =
-                      fileNameParts.length > 1 ? fileNameParts[1] : fileNameParts[0];
-                  // Keep a script file name in Zone, so when zone.js report 'already loaded'
-                  // error, it can report which file include the loaded zone.js
-                  (Zone as any)[__symbol__('scriptFileName')] = fileNamePart2;
-
                   blackListedStackFrames[zoneAwareFrame2] = FrameType.blackList;
                 }
                 if (fnName.indexOf('runGuarded') !== -1) {
diff --git a/test/common/zone.spec.ts b/test/common/zone.spec.ts
index 68c04037b..e4533cbd4 100644
--- a/test/common/zone.spec.ts
+++ b/test/common/zone.spec.ts
@@ -328,24 +328,12 @@ describe('Zone', function() {
 
       it('should throw when Promise has been patched', () => {
         class WrongPromise {}
-        const errorMessage =
-            'Zone.js has detected that ZoneAwarePromise `(window|global).Promise` ' +
-            'has been overwritten.';
-        const errorScriptMessage = 'the loaded Zone.js script file seems to be';
 
         const ZoneAwarePromise = global.Promise;
         global.Promise = WrongPromise;
         try {
           expect(ZoneAwarePromise).toBeTruthy();
-          try {
-            Zone.assertZonePatched();
-          } catch (error) {
-            expect(error.message).toContain(errorMessage);
-            expect(error.message).toContain(errorScriptMessage);
-            const idx = error.message.lastIndexOf(errorScriptMessage);
-            const fileName: string = error.message.slice(idx + errorScriptMessage.length);
-            expect(fileName).toContain('zone.js');
-          }
+          expect(() => Zone.assertZonePatched()).toThrow();
         } finally {
           // restore it.
           global.Promise = ZoneAwarePromise;