If as a result of the security changes mandated by Microsoft occurring in January and February 2021, your mail application stops retrieving mail, follow the Flow Chart guidance and carry out the appropriate instructions below.

Install the Outlook App (Android/iOS)
See the HYMS How To article:
HYMS Email on Smartphone\Tablet Apps
If iOS/MacOS mail is not retrieving your HYMS Email
1. Delete your HYMS account in Apple mail
2. Add your HYMS mail account in Apple mail
Deleting a mail account in iOS and MacOS
iOS 14
1. Open Settings
2. Tap Mail
3. Tap Accounts
4. Select the email account you want to remove.
5. Tap Delete Account.
6. To confirm, tap Delete Account or, in some cases, tap Delete from My iPhone.
Video of how to remove mail account: Deleting a mail account in iOS 14
Older iOS versions
1. Open Settings.
2. Tap Passwords & Accounts. …
3. Select the email account you want to remove.
4. Tap Delete Account.
5. To confirm, tap Delete Account or, in some cases, tap Delete from My iPhone.
Adding and Deleting a mail account in MacOS
Link to Apple guidance:
Add or remove email accounts in Mail on Mac
If Windows/MacOS Outlook is not retrieving your HYMS Email
1. Delete your HYMS account in Outlook
2. Add your HYMS mail account in Outlook
Deleting a mail profile in Outlook (2016/2019/O365 versions)
Link to Microsoft Guidance:
Remove a Profile
Add your HYMS mail account in Outlook
HYMS How to guide: Connecting to Outlook On and Off Campus
Add Email account to Outlook
NOTE: Outlook 2010 and 2013 will no longer work
Downloading Office 365 (which contains Outlook 365)
See the following How To article:
Downloading Office 365
Accessing HYMS email via a web browser
See the following How To article:
Access your HYMS email via a Web Bowser