# Uncaught ReferenceError - I18n is not defined (after upgrading 1.5 to 1.6)

**URL:** https://meta.discourse.org/t/uncaught-referenceerror-i18n-is-not-defined-after-upgrading-1-5-to-1-6/42334
**Category:** Support
**Created:** [2016 年 4 月 10 日午後 12:47 UTC](https://meta.discourse.org/t/uncaught-referenceerror-i18n-is-not-defined-after-upgrading-1-5-to-1-6/42334 "2016-04-10T12:47:46Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![jongnam](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/jongnam/32/52330_2.png) [@jongnam](https://meta.discourse.org/u/jongnam)
#### Post date: [2016 年 4 月 10 日午後 12:47 UTC](https://meta.discourse.org/t/uncaught-referenceerror-i18n-is-not-defined-after-upgrading-1-5-to-1-6/42334/1 "2016-04-10T12:47:46Z")

</div>

I run Discourse on my own AWS account and it runs on Ubuntu EC2, ElastiCache Redis, and RDS Postgress.

It ran well when using discourse 1.5 and I upgraded to 1.6.

```plaintext
Before: v1.5.0.beta13b +140
After: 1.6.0.beta1

```

After upgrading to 1.6 using `# launcher rebuild app`, the web browser cannot display ant pages. Here is the screenshot of Chrome Developer Tool:

 ![](https://global.discourse-cdn.com/meta/original/3X/e/3/e36f6e3967bba27adf1d06be95aadedea19c08b4.png)

---

<div class="post-metadata">

### Author: ![jongnam](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/jongnam/32/52330_2.png) [@jongnam](https://meta.discourse.org/u/jongnam)
#### Post date: [2016 年 4 月 10 日午後 5:57 UTC](https://meta.discourse.org/t/uncaught-referenceerror-i18n-is-not-defined-after-upgrading-1-5-to-1-6/42334/2 "2016-04-10T17:57:13Z")

</div>

Just fyi, the issue has been resolved after deploying and testing several times. It looks like a temporal issue which may happen one time on a first upgrade.

---

<div class="post-metadata">

### Author: ![codinghorror](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/codinghorror/32/110067_2.png) [@codinghorror](https://meta.discourse.org/u/codinghorror)
#### Post date: [2016 年 4 月 10 日午後 5:59 UTC](https://meta.discourse.org/t/uncaught-referenceerror-i18n-is-not-defined-after-upgrading-1-5-to-1-6/42334/3 "2016-04-10T17:59:52Z")

</div>