Overview
The vast majority of missing email is actually due to email being delivered to places other than the inbox, e.g. spam/junk, Focused Inbox, trash/deleted items, etc. Often, user-implemented email routing rules are the culprit. Email routing rules can be implemented by logging into the email account in a web browser, using desktop email clients, and any device an email account has been configured on.
When looking for a missing email, try searching for the name of the sender, email address of the sender, or a keyword that may be in the email. If you are still unable to locate the missing email, read on for more suggestions.
UW Gmail
To check for email rules in UW Gmail, click here. Review the rules on the email account and if you are experiencing email delivery issues, consider deleting all rules until email delivery issues are resolved. Also check any desktop email clients and devices that have the email account configured and delete or disable all rules, junk mail filtering, etc.
Be sure to check the Spam folder as well as the All Mail folder.
UW Office 365
UW Office 365 has email rules and sweep rules. Review the rules on the email account and if you are experiencing email delivery issues, consider deleting all rules until email delivery issues are resolved. Also check any desktop email clients and devices that have the email account configured and delete or disable all rules, junk mail filtering, etc.
If you have Focused Inbox enabled, be sure to check that folder/tab. Also check the Archive folder.
Recover deleted items in UW Office 365
UW Office 365 has a two-stage Deleted Items system. Deleting an item (email message, contact, etc.) places the item in the Deleted Items folder. Once an item ages out of the Deleted Items folder, it moves to a second-stage Deleted Items folder. To attempt to recover an item from the second-stage Deleted Items folder, follow these instructions.
Learn more about the Recoverable Items folder in Exchange Online