Issue: Missing or Delayed Emails in Office 365

Symptoms:

1. Emails that should be in your inbox are not visible.
2. You receive emails later than expected, even though the sender sent them on time.
3. Important emails from specific senders are consistently missing.

Possible Causes:

1. Email Filtering Rules: Misconfigured email filtering rules can divert emails to folders other than the inbox, causing them to appear missing.
2. Sync Issues: Synchronization problems between devices and email servers can result in emails being delayed or not showing up.
3. Server Delays: Temporary delays on email servers can cause emails to be delivered later than expected.
4. Spam Filters: Aggressive spam filters might flag legitimate emails, causing them to be marked as spam or sent to quarantine.

Resolution Steps:

Step 1: Check Spam/Junk Folders

1. Look in your spam or junk folder to see if the missing emails were filtered as spam.

Step 2: Verify Email Filtering Rules

1. Check if any email filtering rules are misconfigured: a. In Outlook, go to File > Manage Rules & Alerts. b. Review your rules and ensure they are correctly set.

Step 3: Check Sync Settings

1. Ensure your email accounts are set to sync correctly: a. In Outlook, go to File > Account Settings > Account Settings. b. Select the email account and click "Change." c. Check if folders are set to sync and adjust settings if needed.

Step 4: Server Delays

1. If the issue is due to server delays, the emails should eventually arrive. Monitor the situation and see if the delay is resolved over time.

Step 5: Whitelist Important Senders

1. Whitelist known and important senders to prevent their emails from being marked as spam: a. Access your email account settings. b. Look for an option to manage spam or block lists. c. Add email addresses to the whitelist.

Step 6: Check External Email Services

1. If the missing emails are from external senders, check their email service status to ensure there are no ongoing issues.

Step 7: Contact Support

1. If the issue persists, reach out to your organization's IT support or Microsoft support for further assistance.

Please note that these steps are provided as general troubleshooting guidelines. Always refer to official Microsoft support resources for the most accurate and up-to-date guidance on resolving missing or delayed email issues.