If you have added a user to your domain and its not showing up I did this to fix it.
– Make sure Mail Exchange Agent service is started
– in Powershell run
Update-GlobalAddressList -Identity “Default Global Address List”
– In EMC goto organisation / mailbox / offline address book / right click on OAB and update
– On clients that do not sync then goto tools, send/recieve and choose download address book
If you’ve forgotten your BIOS for a HP NC6400 laptop or have a machine that has one set from a previous owner, to clear the password you need disconnect and reconnect the motherboards battery, remove the keyboard, all power and main battery, here are the steps as a video.