Project Online - Administrator has no access to any project after setting up access concept

[JJBru]

Hello,

I am an administrator for a Project Onlne instance. 
After I created and implemented a new access concept with groups for users, categories with allocated projects, users and permissions a fellow administrator has no access to any Enterprise object anymore.

Is there an easy way to restore his permissions without deleting categories. I compared my user's administrator's settings with his - they are the same.
Thanks in advance for help,

[#2]

JJBru --

Please tell me that you DID NOT change the permissions for the default Administrators group. Assuming you did not change these permissions, you should add your fellow administrator to the Administrators group AND remove him from all other security Groups. Hope this helps.