I`d appriciate it if you tell me how I can activate “Enterprise plan” for my collegues. I just payed for three users including mine, thinking let my two collegues who have free accounts use as well, but I have no idea to do it. It seems I have successed to get my account upgraded to the plan though.
I know this is the very basic question but we all just started using BOX and are not used to it. Please tell me if this isn`t a proper way to asking this kind of question.
Dear
I can confirm that your account has been successfully upgraded to an Enterprise plan. If your colleagues have already created free personal accounts, you—as the enterprise admin—can invite them to join your account as managed users. For step-by-step guidance, please refer to this article on Adding Managed Users.
Just a heads-up: you may encounter an error when trying to add existing users. This typically means that the user you are trying to invite already has a personal account associated with that email address.
To resolve, please check out "1 user failed to be added" Message When Adding Managed User.
If you have any further questions or need additional help, please don’t hesitate to reach out. 
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