<p>Try reinstalling Craft. I believe there was another report from a user that had similar JS errors. Try replacing the core Craft files in <code>craft/app</code> and see if that helps.</p>

<p>Craft 2.7.1 was also recently released.</p>

CC BY-SA 4.0
2018-08-28T01:07:37.383Z
Probably worth trying to just clear out `craft/storage/runtime/cache` folder, too.
Brad Bell
CC BY-SA 4.0
2018-08-25T12:25:39.570Z
2018-08-25T12:25:39.570Z
James White
<p>My Control Panel has stopped working since upgrading to Craft v2.7.0. in chrome. I get the following JS error no matter what is clicked in the entry fields and no action is taken. So for example if I want to remove and image and click the minus button nothing happens. If I try and add Matrix fields nothing happens. All of these were working prior to the update.</p>

<blockquote>
  <p>Uncaught TypeError: Cannot read property 'length' of null
      at n.constructor.getWorkingTaskInfo (cp.js:863)
      at n.constructor.setTaskInfo (cp.js:832)</p>
</blockquote>

<p>I'm running on PHP 7.0.13 any ideas?</p>

CC BY-SA 4.0
2018-08-25T10:47:57.420Z
Also just checked it on firefox same issue.
Lettie
CC BY-SA 4.0
2018-08-26T12:51:11.150Z
Tried upgrading to v 2.7.2 and still throwing errors.
Lettie
<control-panel><upgrades><craft2>
Craft 2 JS error in CMS since upgrade to 2.7.0
# Craft 2 JS error in CMS since upgrade to 2.7.0

(Asked by: username_0 on 2018-08-25)

My Control Panel has stopped working since upgrading to Craft v2.7.0. in chrome. I get the following JS error no matter what is clicked in the entry fields and no action is taken. So for example if I want to remove and image and click the minus button nothing happens. If I try and add Matrix fields nothing happens. All of these were working prior to the update.

> Uncaught TypeError: Cannot read property 'length' of null
> at n.constructor.getWorkingTaskInfo (cp.js:863)
> at n.constructor.setTaskInfo (cp.js:832)

I'm running on PHP 7.0.13 any ideas?

**Tags:** control-panel, upgrades, craft2

> **Comments:**
> **username_0**: Also just checked it on firefox same issue.  
> **username_0**: Tried upgrading to v 2.7.2 and still throwing errors.  

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## 1 answers

### Answer by username_1 on 2018-08-25. Score: 1 | Accepted answer

Try reinstalling Craft. I believe there was another report from a user that had similar JS errors. Try replacing the core Craft files in `craft/app` and see if that helps.

Craft 2.7.1 was also recently released.

> **Comments:**
> **username_2**: Probably worth trying to just clear out `craft/storage/runtime/cache` folder, too.  

---

