The website encountered an unexpected error. Please try again later. – after every module install/enable

Hello,

After installing an update of what seems to be every module (i tried “contact_storage” & “yamlform”) my website gets stuck with the known error “The website encountered an unexpected error. Please try again later.”. When this happens i am unable to render ANY page on my website meaning i cannot log in to admin pages either. I was stuck on this situation first, but after consulting comparable threads i have been able to resolve the issue by deleting the newly installed folder on my ftp server and clearing the cache in the db manually through phpmyadmin.

At one point even that wouldnt help me and i was forced to revive from a backup.

I made a clean install and tried it again, the same thing seems to happen. Again i forced the removal of the module manually and got to the admin pages to get to the logs.

I make use of a level+ theme (for drupal 8) supplied from: http://www.morethanthemes.com/themes/levelplus. I am running the latest version of drupal 8x (updated it today)

Below is the sequence of the log files:

php 12/06/2016 – 01:57 DrupalCoreDatabaseDatabaseExceptionWrapper: SQLSTATE… admin
php 12/06/2016 – 01:57 DrupalCoreDatabaseDatabaseExceptionWrapper: SQLSTATE… admin
php 12/06/2016 – 01:57 Warning: Error while sending QUERY packet. PID=11764 in… admin
system 12/06/2016 – 01:57 yamlform_ui-module geïnstalleerd. admin

You can see that it gets installed and then renders some errors. I have put them chronologicly in a text file that you can acces: HERE

I have spent today 8 hours after my job trying to figure this out, but i only wasted my time and now am back to start :s Any help is much appreciated!

Drupal version: 


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