How to troubleshoot errors after successful Drupal update? Recently, I updated a Drupal core website from 7.31 to 7.34 and the process was successful, without any error during the upgrade.

It's showing the latest version of 7.34 core in the Status Report, BUT if I visit the home page or any other pages, then it's showing different different errors.

I can access the Administration pages BUT I don't know how to solve these issues.

Here you can see the details about it:


http://cityguest.norrwing.ro/en
http://cityguest.norrwing.ro/en/privacy-policy


I appreciate your help in advance!
According to this comment you should re-upload common.inc file in includes folder.


  I don't use Drupal Commons, but I got the same error when upgrading
  Drupal Crore from 7.20 to 7.34.
  
  This function was added in Drupal Core 7.33 so check your core version
  is later than that. https://www.drupal.org/node/2369141
  
  I then fixed it by reuploading common.inc in the includes folder. Must
  have not uploaded correctly the first time.