The ControlPoint Online solution occasionally fails to create the ControlPoint Configuration Site when it is added to the SharePoint Online environment OR user is not explicitly defined as a site collection administrator. NOTE: Permission must be explicit so user cannot be in a group given site collection administrator rights.
If ControlPoint Online has been installed, but the Configuration Site cannot be accessed, check the following:
The global administrator does not have the same permissions and will only work if the account is also explicitly listed as a site collection administrator. NOTE: This will not work if the user is only a member of an AD group with site collection administrator rights.
Users with Full Control over the site will not have enough permissions to log in.
The URL name must be cpconfig.
The template, which is added with the ControlPoint Online solution, must be CPConfigSite.
The rest of the site options can be left as default.