We create a Google page for our company. After a few days we received a letter from Google to validate our company. A code was written to this letter and we used this like asked.
The code was well validated and since this moment we can not access to our company page via Google+. Error 500 : The system has encountered a problem.
We do not know who to contact nor what this error mean.
Google+ Pages are now part of a program called Google My Business, it has its own support center -> https://support.google.com/business/.
Regarding the Error 500, it is a standard code error for web sites. From List of HTTP status codes
500 Internal Server Error
A generic error message, given when an unexpected condition was encountered and no more specific message is suitable.
By the other hand Google has a apps status dashboard. For September 11, 2015 it shows an ongoing issue with several services. Maybe its related to your Google+ page problem.
