Error editing GPO settings

Error editing GPO settings

Hello,

When I try to edit a GPO by clicking on the "Edit GPO Settings" option, I get the following error:

      

It happens with all the GPOs even the ones created directly from ADManager Plus. I can correctly do other actions like create/delete GPOs, enable/disable user and computer settings, enable/disable/remove GPO links but I can't edit the settings. According to the error message, it looks like a permission problem with the account that is used to connect to the domain but I don't find which one. What permissions are necessary to edit GPOs from ADManager Plus?

Thank you.
                New to ADManager Plus?

                  New to ADSelfService Plus?