Update from 8.1.3 to 8.1.7 gives me a fatal error on most pages After attempting to update to version 8.1.5 I received the


"The website encountered an unexpected error. Please try again later."


error on many pages. I also get the following error in Recent Log Messages;


"Drupal\Component\Plugin\Exception\PluginNotFoundException: The "2" plugin does not exist. in Drupal\Core\Plugin\DefaultPluginManager->doGetDefinition() (line 52 of   /home/username/public_html/domain/core/lib/Drupal/Component/Plugin/Discovery/DiscoveryTrait.php).


Any ideas what could be causing this or how to fix it?

Update 2016/07/20

I just tried once again to update from 8.1.3 to 8.1.7 and am getting the same errors. My 8.1.3 site was stable with no errors.

Specifically, the site has the following issues after updating and after running update.php several times.


non-admin users can't log in; they receive the white screen of death upon login attempt, and can't even navigate to a different page than the default user page. The can only successfully logout using /user/logout to get back to the working frontpage and other working content pages.
when logged in as admin, eveything seems to work except for the "extend" and "people" admin tabs, which result in a wsod.


The reports details show the following information after an unsuccessful attempt to access;



Type php 

Date Wednesday, July 20, 2016 - 08:09 

User admin 

Location http://www.domain.com/admin/people 

Referrer http://www.domain.com/admin/config/people/accounts 

Message Drupal\Component\Plugin\Exception\PluginNotFoundException: The "2" plugin does not exist. in Drupal\Core\Plugin\DefaultPluginManager->doGetDefinition() (line 52 of /home/username/public_html/domainfolder/core/lib/Drupal/Component/Plugin/Discovery/DiscoveryTrait.php). 

Severity Error 

Hostname @@@.@@.@@@.@@@ 

Operations



Type
page not found 

Date
Wednesday, July 20, 2016 - 11:34 

User
admin 

Location
http://domain.com/quickedit/metadata 

Referrer
http://domain.com/node/preview/aabc334a-08fb-4d6a-8672-281dbe7a56e6/default 

Message
/quickedit/metadata 

Severity
Warning 

Hostname
113.37.159.155 

Operations



Type
php 

Date
Wednesday, July 20, 2016 - 11:25 

User
admin 

Location
http://domain.com/node/add/lesson 

Referrer
http://domain.com/speakraku 

Message
Warning: mkdir(): File exists in Drupal\Component\PhpStorage\FileStorage->createDirectory() (line 165 of /home/username/public_html/domain/core/lib/Drupal/Component/PhpStorage/FileStorage.php). 

Severity
Warning 

Hostname
113.37.159.155 

Operations
Fixed - tracked the problem down to the dev version of field permissions I was using. Updated to the latest dev version and all related issues were resolved.