Client user working with Task

We have setup Zoho projects to work with one of our clients and have a number of contractors and clients attached to the project.

One of the clients is an internal developer that has task assigned to him, but he said there is not a way from him to see just his task. They are not showing up. I've checked and the milestone is external.

Should I have set him up as a contractor?

Also, he keeps getting a message that he hasn't responded to the confirmation email, but following the information in the help are he can't find where to resend it.

Thank you for any help on this. This is a nice system and I would like to continue to use it.