Outlook, once organized with Exchange server profile in Cached Exchange Mode, creates AN OST or Offline Folder file. This OST file is encrypted with a novel MAPIEntryID GUID key, that is keep within the written record of your native system and Exchange server. though Outlook OST file permits users to figure even once the system is offline, it must manifest the user profile by matching the MAPIEntryID GUID key with the server mailbox a minimum of once to permit access to OST and Outlook profile.

However, once this authentication fails, Outlook cannot connect with the Exchange server mailbox and displays the subsequent or similar error message.

Cannot begin Microsoft Outlook. Cannot Open Outlook Window. The set of folders can not be opened. The file C:\Users\….\[email protected] can not be accessed. you want to connect with Microsoft Exchange a minimum of once before you’ll use your Outlook file (.ost).

Why Outlook isn’t Connecting to Server?

Outlook could fail to attach to the Exchange server because of numerous reasons, such as:
Connectivity problems
OST synchronization errors
Damaged OST file
A deleted or disabled mailbox from the Exchange server
Damaged Microsoft workplace or Outlook program files
Corrupt Outlook profile
Incompatible or faulty add-ins
Methods to Resolve Outlook Cannot connect with Server Error
You can fix Outlook not connecting to server problems in Windows by following the given ways. These ways work on Outlook 2007, 2010, 2013, 2016, and 2019.

However, you must backup your OST file to a safer location before applying these ways. this may facilitate stop permanent information loss if these fixes don’t work for you.

IMPORTANT NOTE: If your mailbox is disabled or deleted from the server, the subsequent solutions won’t work. In such a case, the OST file enters the unparented stage and becomes inaccessible. However, you’ll convert such OST file to PST or export the OST file on to a brand new or existing live Exchange mailbox or workplace 365 account victimisation Stellar device for OST . The tool also can assist you restore missing or deleted mail things.

Method 1: Restart System and Check net affiliation

A simple system restart will typically do magic! It will resolve problems with Windows and different applications. thus begin by restarting your system. Then check the net affiliation and begin Outlook.

If you continue to see identical error message and Outlook cannot connect with the server, follow future technique.

Method 2: Disable Add-ins
Incompatible or faulty Outlook add-ins could stop or disrupt Outlook reference to the Exchange server. to envision if the error is caused by a faulty add-in, follow these steps:

Press Windows + R keys, kind Outlook /safe, and press the Enter key or click ‘OK.’ this may open the Outlook in safe mode.

Click File > choices.

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

Uncheck all Add-Ins and so click ‘OK.’

Restart Outlook in traditional mode.
If the error is resolved, activate every add-in, one-at-a-time, and observe Outlook for the error. this may assist you notice and take away the faulty add-ins.

However, if the error still seems once you open Outlook, follow future technique.

Method 3: produce a brand new Outlook Profile
Outlook could fail to attach to the Exchange server because of authentication failure, if your profile gets broken. In such a case, you’ll produce a brand new Outlook profile to mend the error. The steps square measure as follows:

Open instrument panel and search ‘Mail.’ Then click on the ‘Mail’ choice.

Restart Outlook in traditional mode.
If the error is resolved, activate every add-in, one-at-a-time, and observe Outlook for the error. this may assist you notice and take away the faulty add-ins.

However, if the error still seems once you open Outlook, follow future technique.

Method 3: produce a brand new Outlook Profile
Outlook could fail to attach to the Exchange server because of authentication failure, if your profile gets broken. In such a case, you’ll produce a brand new Outlook profile to mend the error. The steps square measure as follows:

Open instrument panel and search ‘Mail.’ Then click on the ‘Mail’ choice.

Restart Outlook in traditional mode.
If the error is resolved, activate every add-in, one-at-a-time, and observe Outlook for the error. this may assist you notice and take away the faulty add-ins.

However, if the error still seems once you open Outlook, follow future technique.

Method 3: produce a brand new Outlook Profile
Outlook could fail to attach to the Exchange server because of authentication failure, if your profile gets broken. In such a case, you’ll produce a brand new Outlook profile to mend the error. The steps square measure as follows:

Open instrument panel and search ‘Mail.’ Then click on the ‘Mail’ choice.

Click ‘Show Profiles‘ and so click ‘Add….‘

Enter the Profile Name and click on ‘OK.’

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

This will produce a brand new Outlook profile.
Now open Outlook, select the new Outlook profile and set up it. Then check if you’ll access the Outlook and mailbox things from the OST file. If not, head to future technique.

Method 4: put in Microsoft workplace
Damaged or corrupt Microsoft Outlook or workplace program files also can result in property errors. you’ll resolve this by repairing or reinstalling the MS workplace program.

Steps to repair MS workplace installation:

Open instrument panel and click on Uninstall a program.

Select Microsoft workplace program and so click ‘Change.‘

Select ‘Repair’ and so click ‘Continue’ to repair the MS workplace.

Now attempt gap MS Outlook. If this doesn’t resolve Outlook cannot connect with server issue, you’ll attempt reinstalling the MS workplace.

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

Download the workplace uninstall support tool and launch it.

Click ‘Install.‘ once the installation, it’ll launch the ‘Microsoft Support and Recovery Assistant‘ utility.

Click ‘I agree.’

Select the workplace version you would like to uninstall and click on ‘Next.’

Follow the wizard to uninstall MS workplace and so restart your system.
The tool can open up mechanically and end the uninstall method.
Then choose the MS workplace version you would like to put in and follow the wizard.
You may conjointly transfer the MS workplace setup and install it manually. Then open the MS Outlook, set up your email profile, and check if your Outlook is currently connecting to the Exchange server and dealing. If not, follow future technique.

Method 5: reconstruct or Recreate OST file
If the on top of solutions failed to work for you, attempt recreating the Outlook file, i.e., OST. you’ll do that by either deleting, moving, or renaming the present OST file. By default, the OST file is found at C:\Users\UserName\AppDataLocal\Microsoft\Outlook\. However, the OST file location could vary supported the Outlook version. For additional details, check our guide to find the OST file.

Once found, delete, move, or rename the file with the .old or .bak extension. currently open Outlook. If your profile and therefore the mailbox on the server square measure still active, a brand new OST file are going to be created and mail things are going to be synchronous from the server.

But if the OST file isn’t recreated, it indicates a disabled or deleted mailbox or profile. In such a case, you can’t do a lot of however convert the unparented OST file to PST format victimisation the OST to PST device tool , as mentioned earlier. Then import the PST file into your new Outlook account.