Open Outlook and click: File - Account Settings - Delegate Access. Click on the name you would like to remove ie, All@ceg.co.uk or whichever delegate you have set, then click remove.

Changed autodiscover A record  on 123-reg to CNAME pointing to autodiscover.outlook.com. Once DNS has updated, autodiscover works correctly.

Mimecast is our email protection, filter and archive system which operates BEFORE items reach your CEG Outlook inbox and acts as our first line of defense against spam and malicious emails. It also provides a much greater range of protection that is beyond the scope of this quick tutorial.   To access Mimecast from your Outlook software, follow the instructions below.   In Outlook on the menu bar - click the Mimecast item.     There are various options such as Online Inbox , On Hold Messages and Block Senders.     Online Inbox shows ALL your emails ever received (although it defaults to just one year) and they cannot be deleted. On Hold Messages shows emails that have been detected as spam and they won't be released into your Outlook inbox unless released from here. Block senders lets you block entire domains or individual email addresses from ever contacting you. Please be wary of the domain block, if you decided to block person@gmail.com and chose domain - you will never receive any emails from a gmail address again unless it is removed from the block list.

To re-enable the Teams Meeting add-in: In Outlook, select File > Options > Add-ins > Manage, select “Disabled items”, and then Go. If you see Teams listed under Disabled Items, select it and then select Enable. Restart Outlook and confirm if the add-in is working.