Select Manage Members from the control panel

Located on the right is a link which says Add Member.

Once you select this link you are provided an area to enter member details. Submitting these details will allow the user to login. You must contact the user to provide their credentials.  

When is this useful?

This form allows you to bypass the regular means of inviting a member in case an invitee is having trouble receiving or processing a invitation. Enter their Full Name and Credentials as well as what groups you would like them to be in. Don't forget to communicate this information to the person and remind them to change their password once they sign in.

Tips

Keep in mind that if the email address you are attempting to add is already registered to any Igloo community the password you specify will not be the active password for this members login. Instead it remains the most recent password the member set for their account. Since in some situations the user will not be aware of their password, direct the member to use the forgot password function of your community to gain access to the community.