[SOLVED] Microsoft Teams Error Code 42B

Are you trying to open Microsoft Teams so that you may join in a meeting, but the application, instead of successfully logging you in, has frozen on an error screen displaying the error number 42b? Then you are in the right place. Here you will find some of the best ways to fix Microsoft Teams error code 42B problem pretty easily.

Problem code 6 in Microsoft Teams would be a sign-in issue that prohibits you from login into your Teams account. This error may occur if you are using a slow internet connection, VPN service, proxy network, and so on.


Even though the causes of this error code are not entirely understood, we have some potential solutions for you to try that have, according to reports from other users, been successful in resolving the issue.

Let us investigate the situation right now and uncover the answers, shall we?

Reasons Behind Microsoft Teams Error Code 42B

The error code 42b for Microsoft Teams indicates that the application is unable to sign you into its server successfully. Utilization of a Virtual Private Network (VPN) or a Proxy Server, as well as the presence of useless cache files, are the primary contributors to the Microsoft Teams error code 42b.

Additionally, the error code 42b is triggered in Microsoft Teams when the credentials for the Microsoft account are removed from the Windows account manager and when there are multiple active sessions of the application.

We have identified several potential causes for the error code 42b that is generated by Microsoft Teams. Those are mostly associated with the internet settings on your computer as well as the Windows configuration settings.

In the following breakdown, you will get a complete rundown of the many causes that might be responsible for the error code that MS Teams gave you. Among all of these, you should look for the one responsible for your problem.

Error code 42b in Microsoft Teams may thus be linked to the following reasons:

Unnecessary Excessive Cache Files

To carry out its procedures in Windows, every software generates temporary cache files. When you use a multipurpose program like Microsoft Teams for even a short period, you end up accumulating a significant quantity of trash in the form of cache files.

Older cache files of the application become outdated after a session has been closed or after you have changed your credentials, such as the password. This causes the application’s background activities to become disrupted.

This conflict may be the source of the error number 42b on MS Teams, which results in issues while attempting to sign in to the application.

VPN Is Turned On

The cause of error code 42b in Microsoft Teams may lie in the fact that you are connecting to the service using a virtual private network (VPN).

To get the information associated with your account, MS Teams demands that you maintain a constant connection with its server. When you use a virtual private network (VPN), this connection is slowed down, and the real-time data transfer that occurs between your Microsoft Teams client and the server is interrupted.

Because of this, logging in to the Microsoft Teams account will fail with the error number 42b if you use a virtual private network (VPN).

Interruptions From Other Apps Or Temporary Glitches in MS Teams

Error code 42b is shown if the background processes of the Microsoft teams are disrupted during the starting process by the activities of another application. This prevents the Microsoft teams from performing properly and causes errors to occur.

The same is true for the occasional malfunctions of windows, which not only disrupt the teams’ background operations but also cause it to display the error number 42b.

Performing a variety of procedures in the background on a corporate communication platform like Microsoft Teams is necessary to ensure that users always have access to all of their available options.

The error code 42b will be shown if the program fails to work properly because it is forced to terminate some processes due to other applications or a RAM optimizer.

Several Active Sessions of the Teams App

The error number 42b will appear on your screen if you are signed in to Microsoft Teams on several devices while the sessions on those devices are ongoing. This means that Microsoft Teams is unable to sync the activities taking place across all of your devices with your account.

Because of this, attempting to log in to MS Teams from multiple devices would result in error number 42b being shown on the Microsoft Teams app.

Microsoft Teams Account Is Unlisted in Windows

You may run into the Microsoft Teams error code 42b if the Microsoft Teams account isn’t registered in the Windows account management or if there is a problem with how they sync with one another.

Information on your computer can be synchronized thanks to Microsoft Teams and the Windows Accounts Manager. If the synchronization process is disrupted, it will prevent your account from signing in to the application and display the error number 42b.

How To Fix Microsoft Teams Error Code 42B

Now, in this part, we will be showing you some of the most effective ways to fix this MS Teams error code 42B problem. However, take your time and don’t rush into putting the options into action just yet since one incorrect move might make your problems much more difficult to handle.

Now, without further ado, let’s get your error 42b resolved and see whether it still occurs.

The following is a list of possible solutions for the error number 42b that occurs in Microsoft Teams:

1. End the Task And Reopen The Microsoft Teams App

Because of various hiccups and occasional problems, Microsoft Teams may sometimes malfunction and report the error number 42b when it does so. It’s because Windows has several processes running in the background at the same time.

By exiting and then relaunching the application, these small bugs may be fixed, and the background operation of the Teams app can be restarted seamlessly.

If you want to close the Microsoft Teams app correctly, follow the steps below.

  • Right-click on the Start button and choose Task Manager, or press Ctrl + Shift + Esc button on your keyboard to do the same.
  • Locate the Microsoft Teams app and End Task it.


Now open the MS Teams app once again and see if the problem persists or not.

2. Disable VPN and Proxy Server

In the corporate world, Microsoft Teams is an instant messaging system. To carry out the user’s orders, it is necessary to maintain continuous contact with the distant server. Its connectivity can be disrupted if a virtual private network (VPN) or proxy server connection is present since these networks cause the connection to take longer.

Therefore, to prevent problems such as the Microsoft Team error code 42b from occurring, make sure that your VPN and proxy servers are turned off in the network settings of your device.

Additionally, it will assist you in avoiding additional problem codes that may appear inside the Teams application. If you want to prevent problems like this one, you should use a direct connection instead of a proxy server or a virtual private network (VPN).

3. Delete Microsoft Teams Cache Files

After you have changed the password for your Microsoft account, you may be able to fix the Microsoft Teams error number 42b by clearing the cache files for the MS Teams app. It will delete all of the temporary information that was previously saved about your log-in sessions and will reactivate the application’s processes.

To fix this issue, you will need to erase the cache that is stored on your device in the Microsoft Teams application.

Clearing the cache on your device for Teams may be done in a few simple steps, which are as follows:

  • Click the right mouse button on the Start
  • Select Task Manager from the menu.
  • Search the Microsoft Teams process, and then click on it.
  • Click on the End Task button on the upper sanction if you are a Windows 11 insider preview user, or you can find the End Task button in the below right side corner.


  • To launch the Run application, press the Win + R key simultaneously on your keyboard.
  • In the box, type %appdata%\Microsoft\teams, and then click the Enter key on your keyboard.
  • Delete the folders that have the following names: application cache, blob_storage, Cache, databases, GPUcache, IndexedDB, Local Storage, and tmp.


You will need to restart your computer and then open Microsoft Teams. Check to see if the problem persists or not.

4. Re-Add Microsoft Teams Account in Windows

The Microsoft Teams error number 42b can be fixed by re-establishing the connection to your MS Teams account using the Windows Account Manager. It permits for Microsoft Teams to account for themselves under the manager of accounts.

Follow these steps to rejoin your user accounts for MS Teams in the Settings app for Windows 11:

  • Go to the settings by clicking on the Start button on Taskbar and selecting Settings. Or press the Win + I button on your keyboard to do the same.
  • Navigate to Accounts > Access work or school, and search for the account that you are using to sign in to MS Teams.
  • Now press on Disconnect button on that account and confirm it by pressing Yes.


  • After disconnecting the account, hit the Add button to re-add that account once again.

Once you are done completing all the steps above, clear the cache files of MS Teams and check to see if the problem still arrives or not.

5. Close All The Active Sessions of the Microsoft Teams App In Other Devices

Imagine that you are running Microsoft Teams on several different devices and that you have numerous active sessions going at the same time. In such a scenario, the Microsoft Teams app fails to synchronize the activities that are taking place across several devices and shows the error number 42b.

Therefore, to resolve the problem with the error code 42b in Microsoft Teams, you will need to log out of all of the current sessions of the application, except the session running on the device that serves as your main device.

After doing that, check to see if that helps to solve your problem or not.

6. Uninstall & Reinstall MS Teams

Error number 42b on Microsoft Teams might be fixed by completely uninstalling and then reinstalling the Microsoft Teams software.

But only do this after following all the methods above and still can’t fix the issue.

Performing a reinstallation of your Microsoft Teams can be accomplished in a few easy steps, as shown below:

  • Press the Win + I button on your keyboard to open Settings Alternatively, you can click the Start menu and go to Settings.
  • Navigate to Apps > Installed Apps.
  • Search for Microsoft Teams and click on the three-dot button on the right side.
  • Now uninstall it by selecting the Uninstall


Now your MS Teams has been uninstalled completely. Go to the official website of Teams and download the setup file and install it as usual.


Reading the topics you just went over should have made it clear to you all of the challenges and problems that are associated with the Microsoft Teams error code caa5004b. Therefore, if you have the impression that you are capable of handling the situation on your own, then you should proceed to put the answers into action. We hope this article has helped you solve the MS Teams’ error code 42B problem pretty easily.