Editor’s note on March 18, 2019: This Outlook article was first published in September 2013. Since then, we have added a video tutorial, updated steps in the Rebuild section, and updated the related resources.

Microsoft Outlook is often rendered useless because it cannot connect to its Exchange server. Sometimes troubleshooting the issue is as simple as closing Outlook and restarting. In other instances, troubleshooting is much more challenging…or so it seems.

SEE: How to work from home: IT pro’s guidebook to telecommuting and remote work (TechRepublic Premium)

The following step-by-step instructions make solving that connectivity loss a snap. These instructions don’t require a computer science degree to understand them, so just about anyone should be able to get MS Outlook re-connected to their Exchange server. We’ll start with the simplest tip and increase the difficulty as we go along.

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Uncheck offline mode

Oftentimes when a client calls and says, “My email won’t work!” I find that Outlook was somehow set to offline mode. If you’re using Outlook 2007 or earlier, click the File menu. If there is a check mark next to Work Offline, uncheck it, and you should be good to go.

If you’re using Outlook 2010 or higher, follow these steps:

  1. Click the Send/Receive tab.
  2. Locate the Work Offline button.
  3. Click the Offline button.

At the bottom of your Outlook window, you should see Trying To Connect…. If it connects, your problem is resolved; if not, move on to the next solution.

SEE: How to save time and expand features with Office add-ins (free PDF) (TechRepublic)


You should restart MS Outlook and, if that fails, restart your computer. I cannot tell you how many times I’ve seen Outlook connectivity issues resolve with a simple restart. The issue could be caused by the computer having connectivity issues. If you open your web browser and cannot reach a website or internal resources, that’s most likely the problem.

If Outlook still cannot connect and you cannot reach any websites or internal resources, contact your IT department because you have a networking issue. Once that is solved, Outlook will be fine.

SEE: Cost comparison calculator: G Suite vs. Office 365 (Tech Pro Research)


Outlook can use two types of data files (.pst and .ost), and both are susceptible to errors that can cause connectivity problems. Here’s how I handle this:

  1. Close Outlook.
  2. Open the Control Panel.
  3. Locate the Mail icon (depending on how Windows Explorer is set up, you might have to click the Users section to find the Mail icon).
  4. In the resulting window, click Data Files.
  5. Select your data file from the list and click Open File Location (Figure A).
  6. Locate the data file in question (it will probably have the same name as your email address).
  7. If the file has the extension .ost, rename the extension to .OLD. If the file has the extension .pst, do nothing at this time.
  8. Close these windows and open Outlook.

Figure A

This window will list all data files in use with Outlook.

Note: You need to be able to see file extensions in order to know if your data file is a .pst or .ost. This is handled through Windows Explorer settings.

If your data file is a .pst, follow these steps to run Scanpst on the file:

Close Outlook and browse to one of these locations:

If you use Outlook 2019 – C:Program Files (x86)Microsoft Office

If you use Outlook 2016 – C:Program Files (x86)Microsoft Office

If you use Outlook 2013 – C:Program Files (x86)Microsoft OfficeOffice15
If you use Outlook 2010 – C:Program Files (x86)Microsoft OfficeOffice14
If you use Outlook 2007 – C:Program Files (x86)Microsoft OfficeOffice12

Once inside that folder, follow these steps:

  1. Double-click on the SCANPST.EXE file.
  2. From the resulting window, click Browse (Figure B).
  3. Locate your .pst file.
  4. Click Start.

Figure B

If you’ve run Scanpst on your data file before, the location will already be in the field.

Scanpst will run eight passes over the data file; depending on the size of your data file, this can take quite awhile. If Scanpst finds errors in the data file, it will prompt you to click the Repair button. You should also check the box for Make Backup Of Scanned File Before Repairing in case something goes awry.

SEE: Six clicks: Outlook shortcuts and secrets to help make you an instant expert (ZDNet)

After the repair is complete, close Scanpst and re-open MS Outlook. If Outlook still cannot connect, move on to the next tip.

Repair install

You can run a repair installation of Microsoft Office; this will solve problems that standard fixes cannot repair. To do this, follow these steps:

  1. Open the Control Panel.
  2. Click Programs and Features.
  3. Locate the entry for your Microsoft Office installation and select it.
  4. Click Change.
  5. Select Repair from the resulting window.
  6. Click Continue.
  7. Allow the repair to complete.
  8. Reboot your computer.

After your computer has rebooted, start Outlook and hope for the best.

Recreate your profile

When all else fails, you can recreate your MS Outlook profile. I prefer to create a new profile (without deleting the old one)–just in case. In order to recreate your profile, you need to know your account setting, so you should have that information before you begin. Here’s how to create a new profile:

  1. Open the Control Panel.
  2. Open Mail.
  3. Click Show Profiles.
  4. Click Add (Figure C).
  5. Give the profile a name.
  6. Walk through the Outlook account setup wizard.
  7. Once the profile is known to work, you’ll either want to set that profile up as the default or delete the old profile.

Figure C

The Outlook profile manager.

If after all of these steps Outlook is still unable to connect, it’s time to call the IT department. It could be a DNS issue, an Exchange issue, or a number of other possibilities that are outside the scope of this article.

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