A Company Administrator or a Company Contact Administrator can add or remove users in his/her own Company in the Contacts Module.
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To see the list of registered external users for the project, select External from the drop down menu in the Contacts List.
To add a new user to the Contacts Register
1. Click Contacts on the Project Bar. 
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Just like adding an already existed company, there are two situations for an existing user: , they exist on the project you are working on or they exist on other iTWO project.
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If you enter an existing account, you will be presented with the following message, you can click Close to add a different one, or or click Use This User to continue.
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