Outlook Not Receiving or Syncing Email? Fixes for Windows

When Outlook stops showing new emails, the first question is whether the messages are reaching your mailbox at all. Open Outlook on the web (outlook.office.com for work accounts or outlook.live.com for personal accounts) or the Outlook app on your phone.

• Emails are there online: the mailbox is fine; the problem is Outlook on your PC. Start at Step 1.
• Emails are missing online too: the problem is with the mailbox or the sender. Start at Step 6.

Step 1: Check connection status and Work Offline (classic Outlook)

Look at the status bar at the bottom of the Outlook window. Messages such as Working Offline, Disconnected or Trying to connect explain everything.

• On the Send / Receive tab, check whether Work Offline is highlighted. If it is, click it to go back online.
• Click Send/Receive All Folders (or press F9) to force a sync.

New Outlook doesn’t have a Work Offline button – if it can’t connect, check your internet connection and try signing out and back in from Settings › Accounts.

Step 2: Restart Outlook and your PC

Fully close Outlook – check the system tray and Task Manager for a lingering OUTLOOK.EXE process – then open it again. If that doesn’t work, restart the PC. It sounds simple, but it resolves many temporary sync and authentication glitches.

Step 3: Update Office

In classic Outlook, go to File › Office Account › Update Options › Update Now. New Outlook updates automatically through the Microsoft Store and Windows. Many sync bugs are fixed by updates.

Step 4: Check for sign-in prompts

If your password changed or your organisation requires you to sign in again, Outlook may be waiting quietly for credentials. Look for a sign-in window hidden behind other windows, or a yellow Need password message in the status bar. Sign in and allow Outlook a few minutes to catch up.

Step 5: Rule out add-ins and the profile

Faulty add-ins and corrupted profiles cause many classic-Outlook sync problems. Start Outlook in Safe Mode, which disables add-ins, by following our guide to Outlook Safe Mode and creating a new profile. If email syncs correctly in Safe Mode, an add-in is responsible. If not, creating a new profile often fixes it.

Step 6: Check whether your mailbox is full

A full mailbox can stop new messages arriving, and senders may receive a bounce message.

• Outlook on the web: open Settings and look for the storage section to see how much space is used.
• Classic Outlook: File › Info › Mailbox Settings shows mailbox size and options to clean up.

Empty Deleted Items and Junk Email, and delete or archive large messages. Sorting by size helps find the biggest culprits.

Step 7: Check Junk, Focused Inbox and rules

Messages may be arriving and simply being filed somewhere unexpected.

• Look in Junk Email and, if Focused Inbox is on, the Other tab.
• Use search for the sender’s address across All folders.
• Review rules (classic Outlook: File › Manage Rules & Alerts; Outlook on the web and new Outlook: Settings › Mail › Rules). A rule moving or deleting messages is a common cause after reorganising folders.
• Check blocked senders in your junk email settings.

Unexpected rules that forward or delete mail can be a sign that someone else has accessed your account. If you find a rule you didn’t create, change your password, turn on two-factor authentication and, for work accounts, tell your IT team.

Step 8: Shared mailboxes and large folders (classic Outlook)

In Cached Exchange Mode, classic Outlook keeps a local copy of your mailbox. If one folder won’t update, right-click it, choose Properties › Clear Offline Items, then click Send/Receive to download it again. This only clears the local copy, not messages on the server.

You can also check File › Account Settings › Account Settings, double-click your account and review the Download email for the past slider – older messages beyond that period are only available online.

Step 9: Check for a service outage

If nothing works and colleagues have the same problem, the issue may be on Microsoft’s side. Personal users can check Microsoft’s service status page; business users should contact their IT team or Microsoft 365 administrator, who can check Service health in the admin centre.

Step 10: Repair Office

Classic Outlook can be repaired from Settings › Apps › Installed apps: find your Microsoft 365 or Office entry, choose Modify, and select Quick Repair. If that doesn’t help, try Online Repair, which reinstalls Office and takes longer.

Conclusion

Start by checking Outlook on the web: if email is arriving there, the problem is local and is usually fixed by going back online, restarting, updating, or a new profile. If it isn’t arriving, look at mailbox storage, rules, junk filters and service status. Working in this order gets most people back to a working inbox quickly.