Fix: “The Connection to Microsoft Exchange is Unavailable” Error

Email clients are one of the best ways to manage your email accounts. Although Outlook is a pretty reliable application, you may get an error message saying, “The connection to Microsoft Exchange is unavailable” when you open the application. Besides the application not opening, you will also have no access to any emails from Outlook. 

Usually, a connection issue between Microsoft Exchange Servers and Outlook on your PC gives the error message that says Microsoft Exchange is Unavailable. Below in the article, we have further discussed about the Microsoft Exchange Servers and why it’s unavailable.

What is Microsoft Exchange, And Why is it Unavailable on Outlook?

Microsoft Exchange is a groupware server that offers email hosting, and calendaring servers, for corporate users. Outlook was designed so that users could connect to Exchange servers and collect email from the server.

Outlook and Exchange are designed to work together. Therefore, if some complication arises when connecting with Microsoft Exchange, you are likely to get a Microsoft Exchange unavailable error. 

How to Fix Microsoft Exchange Unavailable Error?

Before we jump into the solutions, make sure you perform general fixes. These fixes include, reopening the application, restarting the PC and checking internet connection. Since it is a connection issue, the issue is very likely to be with your computer.

Therefore first, let us start by flushing the DNS.

Flush DNS

When you flush the DNS, the system clears any IP addresses and records of DNS from the cache. Cache memory filled with multiple IP addresses may cause issues when Outlook tries to connect with Microsoft Exchange Servers. 

To fix this, we recommend that you perform a DNS flush.

1. Press the Windows + R key to open Run.
2. Type cmd and press Ctrl + Shift + Enter to open Command Prompt as Administrator.
3. Type ipconfig /flushdns and press Enter. You should see a message that says, “Successfully flushed the DNS Resolver Cache.”
   
4. Restart your computer and try opening Outlook to see if the issue still persists.

Disable RPC encryption

The RCP or Remote Procedure call is a Microsoft protocol that allows Outlook to access Microsoft Exchange servers. The encryption is done so that hackers cannot access readable emails when Outlook tries to access confidential information from the exchange servers.

Due to encrypting errors, Outlook may face issues connecting with the exchange servers. You can disable RPC encryption on the server side to see if it fixes the issue.

You may think that disabling RPC encryption will make your data vulnerable, but Microsoft also has several other encryption layers that secure your data.

Follow the steps mentioned below to disable RPC encryption.

1. Press the Windows + R key to open Run.
2. Type gpedit.msc to open Group Policy Editor.
3. Navigate to User Configuration > Administrative Templates > Microsoft Outlook “Version number” > Account Settings > Exchange.
4. On the right panel, double-click on Enable RPC encryption.
   
5. Check Disable.
6. Click Apply, and then OK.

Group Policy is not available on Windows Home Edition. To access Group Policy in Windows Home Edition, you need to enable it first.

Restart Microsoft Exchange Service

Outlook requires multiple Microsoft Exchange Services to run in the background. Sometimes, necessary services may not always start correctly, resulting in Outlook giving an error message saying, “connection to Microsoft Exchange is unavailable.”

To fix this, you can try restarting all Microsoft Exchange Services.

1. Press the Windows + R key to open Run.
2. Type services.msc to open the Services window. Here, you will see a list of services that Windows uses.
3. Right click on Microsoft Exchange Services and select Restart.
   

There may be more than one Microsoft Exchange Services running, make sure that you restart them all.

Delete Outlook Profile

The problem that you face may be due to some error when configuring your Outlook profile. If this is true, you can delete your current profile and restart Outlook. Restarting Outlook will automatically create a new profile. 

1. Press Windows + R key to open Run.
2. Type control and press Enter to open the Control Panel.
3. Make sure that View by is set to Large icons.
4. Click on Mail (Microsoft Outlook). Another window named Mail Setup will open.
   
5. Under Profiles, click on Show Profiles.
   
6. Click on Outlook and select Remove.
   
7. Launch Outlook, and the application will provide instructions to create a new profile.

Create a New Profile

You can also create a new profile if deleting a profile does not work. To create a new profile, 

1. Press the Windows + R key to open Run.
2. Type Control and press enter to open the Control Panel.
3. Select Mail (Microsoft Outlook).
   
4. Click on Show Profiles, and then select Add.
   
5. Write a profile name and press OK.
6. Now follow the Account creation process to create a new profile.

Repair Office

Since Outlook is a part of the Microsoft Office Package, you can try repairing Office to check if it fixes any issues. Repairing the Office compares local installation files with its manifest and repairs any corrupt application files, registry values, and dll registration. 

To repair the Office package,

1. Press the Windows + R key to open Run.
2. Type appwiz.cpl and press Enter to open Program and Features.
3. Click on Microsoft Office and select Change.
   
4. Check Quick Repair and press Repair.
   
5. Again, select Repair and wait for the repair process to complete.
   

Import User Shell Folder 

Wrong configuration on the Windows registry may cause the entire Operating System to malfunction. One such setting in the Registry that may cause conflicts with Outlook is the User Shell Folder. The User Shell folder contains important Outlook data that the OS uses to connect to the Microsoft exchange server.

Any changes to the registry may cause the entire OS to malfunction. Therefore before we start, make sure you backup your current registry settings.

To fix this, you need to export the User Shell Folder from a computer that does not give any error message and import it to your PC.

1. Press the Windows + R key to open Run on the PC where Outlook is functional.
2. Type regedit and press Enter to open Registry Editor.
3. Navigate to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders.
   
4. Right-click on User Shell Folder and click Export.
   
5. Name the File as User Shell Folder and select Save.
   
6. Copy this file to the PC where you are getting the error message.
7. Run the .reg file to import the registry configuration.