Microsoft Outlook Problems

Running Slowly

Outlook can be a stand-alone program, such as Outlook 2019, or part of Office 365, which is a constantly updated subscription package. Office 365 contains online and offline versions of Microsoft Office. If you’re doing everything online rather than locally, the performance that you get will depend greatly on the speed of your Internet connection. Outlook mail synchronisation can be particularly affected.

  1. Test your Internet connection speed to see if it’s unusually slow. If Outlook is doing everything online, you can ‘cache’ your e-mails locally for improved speed. See this Microsoft article for information about turning on Cached Exchange Mode.

    In short…

    1. Control Panel
    2. Mail
    3. E-mail Accounts
    4. Select the e-mail account of interest.
    5. Change
    6. Server Settings dialogue appears.
    7. Under Offline Settings tick ‘Use Cached Exchange Mode’.
    8. Select length of time to keep mail offline.
    9. Click the ‘Next >’ button and complete subsequent dialogues.

  2. Check for the presence of malicious software (adware, viruses, Outlook add-ins, browser add-ons, and so on), and consider using alternative browsers.
  3. See if any recent Windows Updates might have affected Outlook.
  4. Check that Outlook is fully updated, because if it isn’t then one of the available updates might improve performance. Outlook 2013 SP1 performed much better that earlier versions.
  5. Make sure that Outlook add-ins are not causing the problem (you can start Outlook in Safe Mode by holding down the ‘Ctrl’ key while double-clicking the Outlook icon, or running ‘outlook /safe’ from the command line).
  6. Look at the mailboxes to see if they are excessively large.

  7. If your e-mail address ends with ‘outlook.com’, ‘hotmail.com’, ‘hotmail.co.uk’, or some other Microsoft-type ending, you might need to change your account settings, because Microsoft have changed the name of their incoming mail server.

    Here’s how…

    1. Tools
    2. Options
    3. Accounts
    4. Select the e-mail account of interest.
    5. Set the incoming server to ‘outlook.office365.com’.
    6. OK

  8. Try using Microsoft’s Office 365 Support and Recovery Assistant, which you can get from here.
  9. Check to see if the ‘AppData’ folder is stored in a network location rather than locally.
  10. Use ‘chkdsk /f’ and ‘sfc /scannow’ to see if there are any problems with the filesystem or the core of Windows itself.
  11. See if the Outlook profile containing the affected account is corrupted, and if it might be, try creating a new Outlook profile and adding the account to that profile.
  12. Check for possible conflicts between Outlook and whatever anti-virus software is installed.
  13. Look in the Application Event Log to see if Outlook is reporting any errors.
  14. See if Outlook AutoArchive is switched on, or if Outlook is synchronising with a mobile device.
  15. If deleting messages is very slow, see if there is a setting to defer the purging of a mailbox until outside normal working hours.
  16. Note that the ‘Download Complete Item Including Attachments’ setting should be turned on.
  17. See these tips if Outlook is not responding.
  18. See these tips if Outlook is running slowly.

Not Receiving Incoming E-mails

  1. See if the user’s data storage allowance on the affected account’s mail server has been exceeded.
  2. Send a test e-mail to the affected account then close and restart Outlook to see if incoming e-mails start arriving.
  3. Look at Outlook’s status bar and make sure that the program isn’t ‘Disconnected’, ‘Trying to connect’, or ‘Working Offline’.
  4. See if incoming e-mails are being put in the ‘Junk’ or ‘Trash’ folders.
  5. Check that the affected account is using IMAP rather than POP, and that no other device is using POP to download then delete incoming e-mails.
  6. See if the Outlook profile containing the affected account is corrupted, and if it might be, try creating a new Outlook profile and adding the account to that profile.
  7. Clear Outlook’s cache.
  8. Find out if incoming e-mails are being redirected somewhere else.
  9. Use the ‘scanpst.exe’ utility to see if the ‘.pst’ (Personal Store) file or ‘.ost’ (Offline Store) file is damaged.
  10. See if any recent Windows Updates might have affected Outlook.
  11. Check that Outlook is fully updated, because if it is not then one of the available updates might fix the problem.
  12. Consider deleting and recreating the affected account (if it’s not a Microsoft Exchange Server account, you might consider using Mozilla Thunderbird to create a safe copy of all the e-mails).
  13. Make sure that Outlook add-ins are not causing the problem (you can start Outlook in Safe Mode by holding down the ‘Ctrl’ key while double-clicking the Outlook icon, or running ‘outlook /safe’ from the command line).
  14. See this Microsoft article for information about repairing Microsoft Office applications, such as Outlook.

Temporarily Increase Priority

  1. Start Task Manager.
  2. Find and right-click Microsoft Outlook.
  3. Click ‘Go to Details’.
  4. Right-click the process.
  5. Click ‘Set priority’.
  6. A priority sub-menu will appear.
  7. Click ‘High’ to increase priority.
  8. A ‘Task Manager’ dialogue will appear, asking if you really want to change the priority.
  9. Click the ‘Change priority’ button.
  10. You have to do this each time you start the computer, so it’s just a temporary measure to speed up Outlook during problem investigation.

Set Computer to Operate with High Performance

  1. Open Control Panel.
  2. Go into ‘Hardware and Sound’.
  3. Go into ‘Power Options’.
  4. Select ‘High performance’.

Compact Outlook Data File

  1. Open Microsoft Outlook.
  2. Click ‘FILE’ near the top of the Outlook window.
  3. The Outlook window will change.
  4. Click ‘Info’ on the left-hand side, if it is not already highlighted.
  5. On the right-hand side ‘Account Information’ will appear.
  6. Click the small rectabgle saying ‘Account Settings’.
  7. A drop-down menu will appear.
  8. Click ‘Account Settings…’.
  9. An ‘Account Settings’ dialogue will appear.
  10. Click the ‘Data Files’ tab if it is not already selected.
  11. Click the e-mail account of interest.
  12. Click ‘Settings…’.
  13. An ‘Outlook Data File’ dialogue will appear.
  14. Click the ‘Compact Now’ button.
  15. A ‘Compact Now’ dialogue will briefly appear.
  16. Within the ‘Compact Now’ dialogue, a ‘Compacting…’ message will appear above a progress bar.
  17. Wait for the compaction process to complete and the ‘Compact Now’ dialogue will disappear.
  18. Click ‘OK’ in the ‘Outlook Data File’ dialogue.
  19. Close the ‘Account Settings’ dialogue.

Remove Unnecessary Add-Ins

  1. Open Microsoft Outlook.
  2. Click ‘FILE’ near the top of the Outlook window.
  3. The Outlook window will change.
  4. Click ‘Options’ on the left-hand side, if it is not already highlighted.
  5. An ‘Outlook Options’ dialogue will appear.
  6. On the left-hand side, click ‘Add-ins’.
  7. A panel will appear on the right-hand side to view and manage add-ins.
  8. Near the bottom of the panel next to ‘Manage:’ and ‘COM Add-ins’, click the ‘Go…’ button.
  9. A ‘COM Add-ins’ dialogue box will appear.
  10. Untick the add-ins that you do not need (nearly all of them except for protection software).
  11. Click the ‘OK button.
  12. Close the ‘Outlook Options’ dialogue.

Updating the Application

  1. FILE
  2. Office Account
  3. Click ‘Update Options’.
  4. A drop-down menu will appear.
  5. Click ‘Update Now’.
  6. Wait for updates to complete.
  7. Restart the computer.

Other Options

    Outlook Options
    Advanced
      RSS Feeds
        Untick two options
      Display
        Untick ‘Disable hardware graphics acceleration’
    Click ‘OK’
      AutoArchive
        Click AutoArchive Settings…’
          Tick ‘Run AutoArchive every’ select number ‘days’
      Click ‘OK’.

Using Office 365 Online

      Whenever you want to access anything, it is going to be looked up at
      ‘outlook.office365.com’.
      You might get pretty bad response times if you ‘ping’ that address,
      so try it.

      (See https://products.office.com/en-us/where-is-your-data-located?geo=All for details.)


      Use ‘nslookup outlook.office365.com’ at a command prompt to see the IP
      addresses where Outlook may be accessing your data.
      Look at your network card (Ethernet or Wi-Fi) to see which DNS server
      is being used.

      (Control Panel > Network and Internet > Network and Sharing Centre >
      Change adapter settings > Find your adapter > Properties > IPV4 >
      Properties > Set a DNS that is going to return better results.)

      Note that Google DNS servers are not recommended because they often return
      wrong or slow servers, or incorrect geo-located servers.Could try 1.1.1.1
      though.
      After changing the DNS, check the response times again using ‘ping’.
      Then use ‘whatismyipaddress.com’ to find out where that IP address
      is physically located.

Other Notes

Make sure that the account of interest uses local ‘.pst’ files rather than ones on the local or wide-area network.