Overview, Apps, and Monitoring Sections Produce Internal Server Errors

Nextcloud version : 14.0.0.19
Operating system and version : Debian 4.9.110-3+deb9u2 (2018-08-13) x86_64
Apache or nginx version : Apache 2.9.1
PHP version: 7.0.30-0+deb9u1

The issue you are facing:
I was transferring my data folder over to a raid array I had set up when I noticed the Overview panel in the Administration section on the left hand side of the settings panel would lead to an internal server error screen and then a little while later Apps stopped working.

Is this the first time you’ve seen this error? : Y

Steps to replicate it:

  1. Fresh install of the version of nextcloud shown above.
  2. Set up and mount a raid array and mount
  3. Set data folder to mounted directory and change config.php and sql database to reflect this
  4. Success

The output of your Nextcloud log in Admin > Logging:

PASTE HERE {"reqId":"W-SzjMCoAZYAAHbL1VUAAAAF","level":3,"time":"2018-11-21T01:23:24+00:00","remoteAddr":"REMOTEADDRESS","user":"admin","app":"index","method":"GET","url":"\/nextcloud\/index.php\/settings\/admin\/overview","message":{"Exception":"Error","Message":"Call to undefined method GuzzleHttp\\Client::request()","Code":0,"Trace":[{"file":"\/path\/to\/nextcloud\/lib\/private\/Updater\/ChangesCheck.php","line":127,"function":"get","class":"OC\\Http\\Client\\Client","type":"->","args":["https:\/\/updates.nextcloud.com\/changelog_server\/?version=14.0.3",{"headers":[]}]},{"file":"\/path\/to\/nextcloud\/lib\/private\/Updater\/ChangesCheck.php","line":73,"function":"queryChangesServer","class":"OC\\Updater\\ChangesCheck","type":"->","args":["https:\/\/updates.nextcloud.com\/changelog_server\/?version=14.0.3",{"id":null,"__class__":"OC\\Updater\\ChangesResult"}]},{"file":"\/path\/to\/nextcloud\/apps\/updatenotification\/lib\/UpdateChecker.php","line":65,"function":"check","class":"OC\\Updater\\ChangesCheck","type":"->","args":["https:\/\/updates.nextcloud.com\/changelog_server\/?version=14.0.3","14.0.3"]},{"file":"\/path\/to\/nextcloud\/apps\/updatenotification\/lib\/Settings\/Admin.php","line":87,"function":"getUpdateState","class":"OCA\\UpdateNotification\\UpdateChecker","type":"->","args":[]},{"file":"\/path\/to\/nextcloud\/settings\/Controller\/CommonSettingsTrait.php","line":115,"function":"getForm","class":"OCA\\UpdateNotification\\Settings\\Admin","type":"->","args":[]},{"file":"\/path\/to\/nextcloud\/settings\/Controller\/AdminSettingsController.php","line":74,"function":"formatSettings","class":"OC\\Settings\\Controller\\AdminSettingsController","type":"->","args":[{"10":[{"__class__":"OC\\Settings\\Admin\\Overview"}],"11":[{"__class__":"OCA\\UpdateNotification\\Settings\\Admin"}]}]},{"file":"\/path\/to\/nextcloud\/settings\/Controller\/CommonSettingsTrait.php","line":126,"function":"getSettings","class":"OC\\Settings\\Controller\\AdminSettingsController","type":"->","args":["overview"]},{"file":"\/path\/to\/nextcloud\/settings\/Controller\/AdminSettingsController.php","line":65,"function":"getIndexResponse","class":"OC\\Settings\\Controller\\AdminSettingsController","type":"->","args":["admin","overview"]},{"file":"\/path\/to\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":166,"function":"index","class":"OC\\Settings\\Controller\\AdminSettingsController","type":"->","args":["overview"]},{"file":"\/path\/to\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":99,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->","args":[{"__class__":"OC\\Settings\\Controller\\AdminSettingsController"},"index"]},{"file":"\/path\/to\/nextcloud\/lib\/private\/AppFramework\/App.php","line":118,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->","args":[{"__class__":"OC\\Settings\\Controller\\AdminSettingsController"},"index"]},{"file":"\/path\/to\/nextcloud\/lib\/private\/AppFramework\/Routing\/RouteActionHandler.php","line":47,"function":"main","class":"OC\\AppFramework\\App","type":"::","args":["OC\\Settings\\Controller\\AdminSettingsController","index",{"__class__":"OC\\AppFramework\\DependencyInjection\\DIContainer"},{"section":"overview","_route":"settings.AdminSettings.index"}]},{"function":"__invoke","class":"OC\\AppFramework\\Routing\\RouteActionHandler","type":"->","args":[{"section":"overview","_route":"settings.AdminSettings.index"}]},{"file":"\/path\/to\/nextcloud\/lib\/private\/Route\/Router.php","line":297,"function":"call_user_func","args":[{"__class__":"OC\\AppFramework\\Routing\\RouteActionHandler"},{"section":"overview","_route":"settings.AdminSettings.index"}]},{"file":"\/path\/to\/nextcloud\/lib\/base.php","line":989,"function":"match","class":"OC\\Route\\Router","type":"->","args":["\/settings\/admin\/overview"]},{"file":"\/path\/to\/nextcloud\/index.php","line":42,"function":"handleRequest","class":"OC","type":"::","args":[]}],"File":"\/path\/to\/nextcloud\/lib\/private\/Http\/Client\/Client.php","Line":161,"CustomMessage":"--"},"userAgent":"Mozilla\/5.0 (Windows NT 10.0; Win64; x64; rv:63.0) Gecko\/20100101 Firefox\/63.0","version":"14.0.0.19"}

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

PASTE HERE <?php
$CONFIG = array (
  'passwordsalt' => 'PASSWORDSALT',
  'secret' => 'SECRET',
  'trusted_domains' => 
  array (
    0 => 'EXAMPLE.COM',
  ),
  'datadirectory' => '/path/to/data',
  'dbtype' => 'mysql',
  'version' => '14.0.0.19',
  'overwrite.cli.url' => 'http://localhost',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'nextcloud_user',
  'dbpassword' => 'DBPASSWORD',
  'installed' => true,
  'instanceid' => 'ocj9yj2a7uft',
  'mail_smtpmode' => 'smtp',
  'mail_smtpauthtype' => 'LOGIN',
  'mail_from_address' => 'noreply',
  'mail_domain' => 'EXAMPLE.COM',
  'mail_smtphost' => 'EXAMPLE.COM',
  'mail_smtpport' => '25',
  'mail_smtpauth' => 1,
  'mail_smtpname' => 'SMTPNAME',
  'mail_smtppassword' => 'SMTPPASS',
);