"Can't update phone" when trying to update to wp 8.1?

[Unregistered]

My phone won't let me update to the new windows 8.1 update. It downloads the update, installs it, gets to the screen with the cogs, stays there for a while with no progress showing on the bar, and then just reboots and displays the message "Can't update phone". I'm running the preview for developers on a Nokia Lumia 820, with plenty of memory on a microSD card availiable.

 

[JamesPTao]

There was a problem for a small subset of people with downloading the update. Microsoft is working on it.

 

[JamesPTao]

But in case you are not one of these because generally they get an error number make sure under the Dev preview app that it is set right. I have heard from others that sometimes after the wp8.1 update that it unchecks itself and the user has to open it back up and reset it. Hope this helps.