Check here: CWIS > Properties > Services > Email Setup > Address Books > Use Network Address Book
If not the above, try if you can see it when logged in as admin, if so we will have to delve into User permissions.
Also try Machine Status > Tools > Troubleshooting > Resets > Software Resets > All Software > Reset > Reset
as it may fix it assuming it is a bug/glitch.
The Network Address Book has disappeared from the options available when you hit "Email" on the touch screen. LDAP is configured and is working properly when testing in LDAP Mapping.
Any ideas? We're done a power cycle.