“You are not a valid mobile phone user”

My environment: UC Manager 7.0.1.11000-3

This is a common error when you try to configure the mobility softkey or line key for Mobile connect.  All you need to do is to configure the “Owner User ID” under “Phone Configuration”. 

If you have extension mobility enabled on that phone, you will find the “Owner User ID” being grey out.  The current work around is to uncheck the extension mobility check box under “Phone configuration”, configure the “Owner User ID”, then recheck the Extension mobility checkbox!