Rather than waiting 24 hours for Outlook to update the Offline Address Book on its own, you can force an update via the Send/Receive menu button.
In general, Outlook will automatically update the Offline Address Book (OAB) for Exchange accounts once every 24 hours.
When it didn’t or when you want to make sure you do have the latest OAB available, you could manually trigger an update from within Outlook as well.
In that case, it is recommended to recreate your mail profile.
When you have Cached Exchange Mode enabled, Outlook by will by default cache the main Global Address List as well.
If the key name doesn’t exist, Outlook uses a value of 8.
Prompt before for full download As the OAB can be quite large in some environments, it could be wise to be prompted when Outlook wants to download the full OAB.This is called the Offline Address Book and is being generated on the Exchange server.Due to various synching schedules, it can take up to 48 hours before you could actually see a change in Outlook after a modification has been made on the Exchange server or in Active Directory.I might have a problem with my Offline Address Book in Outlook.For me, new colleagues are not showing up and the contact pictures aren’t displaying either.This situation however is extremely rare since the default maintenance time on Exchange is at AM and updates and downloads are usually performed during working hours.