Server error in application outlook

Outlook, when configured with Exchange server profile in Cached Exchange Mode, creates an OST or Offline Folder file. This OST file is encrypted with a unique MAPIEntryID GUID key, which is stored in the registry of your local system and Exchange server. Although Outlook OST file allows users to work even when the system is offline, it needs to authenticate the user profile by matching the MAPIEntryID GUID key with the server mailbox at least once to allow access to OST and Outlook profile.

However, when this authentication fails, Outlook cannot connect to the Exchange server mailbox and displays the following or similar error message.

Cannot start Microsoft Outlook. Cannot Open Outlook Window. The set of folders cannot be opened. The file C:Users….abc@xyz.com.ost cannot be accessed. You must connect to Microsoft Exchange at least once before you can use your Outlook data file (.ost).

Why Outlook is Not Connecting to Server?

Outlook may fail to connect to the Exchange server due to various reasons, such as:

• Connectivity issues
• OST synchronization errors
• Damaged OST file
• A deleted or disabled mailbox from the Exchange server
• Damaged Microsoft Office or Outlook program files
• Corrupt Outlook profile
• Incompatible or faulty add-ins

Methods to Resolve Outlook Cannot Connect to Server Error

You can fix Outlook not connecting to server issues in Windows by following the given methods. These methods work on Outlook 2007, 2010, 2013, 2016, and 2019.

However, you should backup your OST file to a safer location before applying these methods. This will help prevent permanent data loss if these fixes do not work for you.

IMPORTANT NOTE: If your mailbox is disabled or deleted from the server, the following solutions will not work. In such a case, the OST file enters the orphaned stage and becomes inaccessible. However, you can convert such OST file to PST or export the OST file directly to a new or existing live Exchange mailbox or Microsoft 365 account using Stellar Converter for OST . The tool can also help you restore missing or deleted mail items.

Method 1: Restart System and Check Internet Connection

A simple system restart can sometimes do magic! It can resolve issues with Windows and other applications. So begin by restarting your system. Then check the internet connection and start Outlook.

If you still see the same error message and Outlook cannot connect to the server, follow the next method.

Method 2: Disable Add-ins

Incompatible or faulty Outlook add-ins may prevent or disrupt Outlook connection with the Exchange server. To check if the error is caused by a faulty add-in, follow these steps:

• Press Windows + R keys, type Outlook /safe, and press the Enter key or click ‘OK.’ This will open the Outlook in safe mode.

• Click File > Options.

• Click ‘Add-Ins‘ and then click the ‘Go…‘ button beside Manage: COM Add-Ins.

• Uncheck all Add-Ins and then click ‘OK.’

• Restart Outlook in normal mode.

If the error is resolved, activate each add-in, one-at-a-time, and observe Outlook for the error. This will help you find and remove the faulty add-ins.

However, if the error still appears when you open Outlook, follow the next method.

Method 3: Create a New Outlook Profile

Outlook may fail to connect to the Exchange server due to authentication failure, if your profile gets damaged. In such a case, you can create a new Outlook profile to fix the error. The steps are as follows:

• Open Control Panel and search ‘Mail.’ Then click on the ‘Mail’ option.

• Click ‘Show Profiles‘ and then click ‘Add….‘

• Enter the Profile Name and click ‘OK.’

• Configure your new profile with your email account and click ‘Finish.‘

• This will create a new Outlook profile.

Now open Outlook, choose the new Outlook profile and configure it. Then check if you can access the Outlook and mailbox items from the OST file. If not, head to the next method.

Method 4: Reinstall Microsoft Office

Damaged or corrupt Microsoft Outlook or Office program files can also lead to connectivity errors. You can resolve this by repairing or reinstalling the MS Office program.

Steps to repair MS Office installation:

• Open Control Panel and click Uninstall a program.

• Select Microsoft Office program and then click ‘Change.‘

• Select ‘Repair’ and then click ‘Continue’ to repair the MS Office.

Now try opening MS Outlook. If this does not resolve Outlook cannot connect to server issue, you can try reinstalling the MS Office.

Steps to uninstall MS Office from the system and install it from scratch:

• Download the Office uninstall support tool and launch it.

• Click ‘Install.‘ After the installation, it will launch the ‘Microsoft Support and Recovery Assistant‘ utility.

• Click ‘I agree.’

• Select the Office version you want to uninstall and click ‘Next.’

• Follow the wizard to uninstall MS Office and then restart your system.
• The tool will reopen automatically and finish the uninstall process.
• Then select the MS Office version you want to install and follow the wizard.

You may also download the MS Office setup and install it manually. Then open the MS Outlook, configure your email profile, and check if your Outlook is now connecting to the Exchange server and working. If not, follow the next method.

Method 5: Rebuild or Recreate OST file

If the above solutions did not work for you, try recreating the Outlook data file, i.e., OST. You can do this by either deleting, moving, or renaming the current OST file. By default, the OST file is located at C:UsersUserNameAppDataLocalMicrosoftOutlook. However, the OST file location may vary based on the Outlook version. For more details, check our guide to locate the OST file.

Once found, delete, move, or rename the file with the .old or .bak extension. Now open Outlook. If your profile and the mailbox on the server are still active, a new OST file will be created and mail items will be synchronized from the server.

But if the OST file is not recreated, it indicates a disabled or deleted mailbox or profile. In such a case, you can’t do much but convert the orphaned OST file to PST format using the OST to PST converter tool , as mentioned earlier. Then import the PST file into your new Outlook account.

Conclusion

The ‘Outlook cannot connect to server’ error may render your Outlook account useless and result in a data loss situation, if not resolved. The error prevents you from accessing the Outlook account and mailbox items as it fails to connect to the Exchange server.

We’ve discussed various methods in this post to troubleshoot the Outlook cannot connecting to the server error. However, if your profile is deleted or disabled from the server, these fixes won’t work. In such a case, you can convert the backup OST file to PST using Stellar Converter for OST. Then import the converted PST into your new Outlook or Exchange profile and restore your mail items. The software also provides options to import the mail items from orphaned or inaccessible OST directly into a live Exchange mailbox or Office 365 or Microsoft 365 account.

Outlook is a personal information manager which is primarily used to fetch emails and is part of Microsoft Office Suite. What makes Outlook different from other email managers is that it has the capability to store notes, includes a calendar, and also a journal. Users might also use it for web surfing.

Outlook has been around for quite a while and is one of Microsoft’s primary products. Despite its popularity, there are several instances where users are not able to connect Outlook to the respected server or get their email active. This is a very common and recurring issue and does not depend on any update whatsoever. In this article, we will go through all the reasons as to why this issue occurs and also what the possible workarounds to fix it are.

What causes Outlook not to Connect?

Outlook is basically a standalone application which attempts to connect to the mail servers periodically. There is also an option to work offline in Outlook. Outlook works by fetching all the emails into local storage and lets you view emails from your computer. However, this might not work if the application itself isn’t able to connect. Here are some of the reasons why this might happen:

If all the above tips don’t work and you are not able to access the internet, you can move on and try to reset the router as explained below:

Before we start resetting the router, you need to note down your router’s configurations. Every ISP has specific settings saved on your router. If we reset the router, these configurations will be lost and you will have another issue at hand. Here, you need to navigate to the IP address associated with your router. This is either present at the backside of the device or in the box of your router. This can be something like ‘192.168.1.2’. If you are unable to find the address, Google your router model and get the information from the web.

1. Search for a button at the back of your router and press it for ~6 seconds until the router turns off and back on signifying the reset.
2. After entering the configurations (if any), connect your console back to the network and check if the failure to initialize the network is solved for good.

Solution 3: Turning Off Work Offline

Outlook has a feature of working offline. This mode is usually turned on by people when they don’t have internet access and still want to make use of Outlook and either check old emails or work on their workspace. In Offline mode, Outlook will not connect to any servers or nor fetch any emails even if the internet is available. Here in this solution, we will navigate to Outlook settings and make sure that Work Offline mode is turned off.

1. Launch Outlook on your computer.
2. Now, click on the tab of Send/Receive and look for the button of Work Offline.
3. If the option is greyed out, it means that the mode is active. Click on it once to deactivate it. Now try connecting and see if the issue is resolved.

Solution 4: Checking for Updates

Before we repair your Outlook account and reset the data files, we will first check whether there are any updates that might be available for Outlook and Windows both. Usually, Office 365 (or normal Office) is updated automatically whenever there is an update available. Office updates are part of Microsoft Updates themselves and you don’t have to do anything.

However, if you have canceled the upcoming update or postponed it manually, Outlook will not be updated to the latest build. Bugs are common throughout all applications even if they are developed by Microsoft. With new updates, along with new features, existing bugs are fixed. In this solution, we will check Outlook and Windows both for potential updates.

1. Launch Outlook. Once you are in the application, click on the File button present at the top-left side of the screen.
2. Now, click on Office Account from the left navigation bar and click on Update Options present at the right side of the screen.
3. If there are any updates, Windows will automatically download and install them on your computer.

It is also recommended that you update Windows to the latest build as well. Windows releases security patches for Office 365 products.

1. Press Windows + S, type “update” in the dialogue box and open the application.
2. Once in the Update settings, click on Check for updates button and wait for Microsoft to connect to servers.
3. If there is any update, it will be downloaded in a while automatically and installed on your computer.
4. Restart your computer after both updates and now try connecting. Check if the issue is resolved.

Solution 5: Repairing Outlook Account

If all the above methods don’t work, we will try repairing your Outlook account on your computer. Here, an Outlook account refers to the information regarding email addresses or servers that you have input in the application. These settings might sometimes be disrupted and hence causes various issues such as the application not connecting. In this solution, we will navigate to Outlook Account settings and manually attempt to repair your account. If there is any issue, Outlook will automatically take care of it.

1. Launch Outlook and click on the File tab present at the top-left side of the screen.
2. Now, click on Info and then select your account from the drop-down. Now, click on Account and Social Network Settings and then click Account Settings.
3. Now, select the Email Address which is causing the issue and click on Repair button present at the top-left side of the screen.
4. You will now be prompted to enter your details or confirm them. It is advised that you remove the password and enter it again. This will eliminate the possibility that you have entered an incorrect password.
5. Press Next. Now, Outlook will automatically try to establish a connection with the servers and then diagnose any issues (if any).
6. After the account is repaired, check if the issue is resolved.

Solution 6: Disabling Extensions

Normally, the majority of the Extensions available for Outlook are by verified developers. However, not all of them work properly and some even conflict with Outlook settings and cause it not to work or connect. Here, what you should do is disable all the extensions and then try connecting. If the connection is successful, it means there was an issue with an extension(s). Then you can enable them one by one and then diagnose which one is causing the problem.

1. Launch Outlook and navigate to File > Options. Click Add-ins from the left navigation bar in the Options.
2. At the bottom of the right-panel, you will the button of Go beside Manage. Click it once.
3. Now, uncheck all the extensions and click OK.
4. Restart the Outlook application and check whether the issue is resolved. If it is, you can follow the procedure to diagnose the troublesome add-in as explained above.

Solution 7: Rebuilding Outlook data file

Before we reinstall/repair the Office 365 installation files, it is worth rebuilding the entire Outlook data file. Outlook saves its data to an external file. This is a type of storage for the application which it uses in its operations. In this solution, we will delete the data file. Then when we launch Outlook, it will instantly notice that the data file is missing and then attempt to recreate it from scratch. This will solve corruption issues (if any).

Before we move on with the solutions, it should be noted that all of your email rules will be removed as a consequence. To export your rules to a location that you import again, later on, follow these steps:

1. Open Outlook and then navigate to the following:

   Home/Rules/Manage Rules

   and then:

   Alerts/Options/Export Rules

2. Now, proceed to export rules for all of your mailboxes to a temporary folder. You will use these backups to import all of your rules back later on when done with the rest of the solution.

Now we can proceed with rebuilding your Outlook Data File:

1. Navigate to Account settings as we did in Solution 5 when repairing the account.
2. Now, click on the tab of Data Files and after selecting the Email account causing problems, click on Open File Location.
3. Now, you can either Rename the file or move it to another location.
4. Now, open Outlook again. It will automatically attempt to rebuild your data file. After it is rebuilt, check if the issue is resolved.

If the issue is resolved, you can import all the rules you exported to the temporary folder and everything will be the same again.

Solution 8: Repairing / Reinstalling Outlook

If all the above methods don’t work and you are still unable to get Outlook working, we can try repairing/reinstalling the application. Here, you should first attempt to repair the suite (Office 365). If the repairing doesn’t work, you can move on and attempt to reinstall it completely.

Note: In the process of reinstalling, you might be required to have to installation executable with you as well as the product key.

1. Press Windows + R, type “appwiz.cpl” in the dialogue box, and press Enter.
2. Once in the application manager, locate the entry of Microsoft Office. Right-click it and select Change.
3. Select the option of Repair from the following window and press Continue.
4. Now follow the on-screen instructions and when the process is complete, restart your computer and check if you can launch and get Outlook to work without any issues.