There are several possible causes when email stops arriving into a user’s Inbox, some of these are preference options that you can set on your inbox
Junk Mail filtering (Office 365)
To keep CCS email clear of spam and security threats, emails are put through algorithms to determine their likelihood of being nefarious. Suspicious messages are sent to a the users “Junk E-Mail” folder instead of their Inbox. There is a small chance that legitimate email messages can be identified as spam and sent to this folder, so you should inspect this folder first if you are late receiving a email you are expecting. It is also good practise to regularly inspect this folder to ensure you are not missing any emails. Your junk mail folder appears alongside your inbox folder.
Conversation View is a feature in Office 365 that, when turned on, messages that share the same subject appear as grouped conversations that can be expanded or collapsed. If conversation view is enabled, try disabling this feature to see if your missing messages appear. See Turn off conversation view
Clutter is a feature of Office 365 that, when turned on, will learn your email reading habits and move less important email into the Clutter folder where they can be reviewed later. Most of the mail going into the folder should be bulk mail (advertisements) and messages from mailing lists. However, if the feature is enabled, you will want to routinely check the Clutter folder, as it may move legitimate mail into this folder. You also receive a regular summary email detailing what has been moved into the Clutter folder. To stop the Clutter process, read Turn Off Clutter. Learning more about clutter here.
Focused Inbox helps you focus on the emails that matter most to you. It separates your inbox into two tabs Focused and Other. Your most important emails are on the Focused tab while the rest remain easily accessible but out of the way on the Other tab. You will be informed about email flowing to Other, and you can switch between tabs at any time to take a quick look. If Focused Inbox is enabled, try disabling this feature to see if your missing messages appear. Turn off focused Inbox.
There are instances when more than one person needs to interact with an Office 365 Inbox. When an account is shared and accessed by multiple people, someone with legitimate access to the account can move or delete messages from the account’s Inbox without making other account users aware of their actions. Ensure a proper workflow is established with the colleagues that you share access to the mailbox with to avoid this problem. If you believe mail is missing from your shared Inbox, confirm with all others who access the account that they have not moved or deleted the mail before contacting the IT Helpdesk.
Outlook needs your password or “Work Offline” is set
When you first run Outlook 2016 on a domain machine, it will ask you to sign in with your school credentials. Often users do not select the “Remember my credentials” option when they do this. After a period of time, their credentials in Outlook will expire and will need to be re-entered to continue receiving new emails. This can give the user the impression that they have stopped receiving emails to their account.
To rectify this, see Outlook – Not receiving emails (Need Password)
You can also set Outlook to “Work Offline”, setting this stops Outlook receiving emails until you turn it off. This is option that can be set under the “send / receive” tab on outlook.
To see how to check for this being turned on see Outlook – Offline or Disconnected
Account is configured in a non-Microsoft client
e.g Android or iOS native mobile mail applications, Apple Mail/Calendar, or Thunderbird
Microsoft’s recommended solution is to remove your configured Office 365 account from any non-Microsoft client and, instead, use official Microsoft clients. Official Outlook clients exist for all major OS platforms. If you try this solution and are still experiencing this issue, please contact the IT Helpdesk.