[SOLVED] Error: Handler with name 'u' already exists

any ideas how to troubleshoot this?

Our app isn’t working right for one of our users in Chrome. It works for him in IE, but not Chrome. He is on the latest version of Chrome, and it worked from him in Chrome a couple days ago.

We had him clear cache and try incognito. He says he is not running any script blockers like Noscript or Ghostery. He says he hasn’t installed any new extensions recently.

Here is the console output, but it’s pretty useless due to minification.

Exception in callback of async function: Error: Handler with name 'u' already exists.
at s._create (https://my.whiterabbitexpress.com/6c2165819848ff7448fc15fd5f3be52f5a83e75b.js?meteor_js_resource=true:186:1648)...

I’m worried that whatever is going on may be affecting other users. But I’m a bit at a loss of how to troubleshoot this mysterious issue.


Same problem here, Firefox no problem; Chrome no go… :frowning:

I’am running Version 51.0.2704.63 (64-bit) of Chrome on Linux a collegue on Windows does not seem to have the same problem, my macbook is currently updating to the latest version… tbc

No idea yet of where to look for a solution

Windows no problem
Linux and OS X no such luck :frowning:

Hi! I have the similar issue.
Today after updating Chrome to latest version I have an Error in browser’s console
"Exception in callback of async function: Error: Handler with name ‘hookWithOptions’ already exists."
and app doesn’t work!

What meteor version you use?

those project is on 1.2.1

I have found some older topics on stackowerflow related to this error
they say that this error is caused by multiple onBeforeAction in Iron Router
I just tryed to comment all onBeforeAction in my code, but it doesn’t change situation

This affect to me as well in meteor 1.3

same? affects one (or some) users, but not all?
you also have same console output in Chrome?

found this

yes, found this too
tryed to delete all onBeforeAction in order to see if they are involved, but nop…
seems like it is something new

We have the same issue. Our app broke for Chrome users… How annoying.

The title should be something like Meteor app crashed after chrome update.

Meteor really needs more practical way to debug production errors. Sourcemaps?

Try this : meteor update iron:middleware-stack

And your problem will definitely resolve.


started getting this in canary, nits is right iron:middleware-stack@1.1.0 does the trick.

I started seeing users get this issue as well starting on 5/25. Turns out that was the same day that Chrome released version 51.0.2704. Once I upgraded to the latest Chrome version on my own machine, the issue came up for me.

iron:middleware-stack@1.1.0 fixed the issue.


iron:middleware-stack@1.1.0 fixed the issue for me too, thanx!

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thanks everyone!
20 chars

omg, thanks everyone! worked like a charm!

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Thank s a lot. It worked for me

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+1 here, it worked for me too!

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