How to Fix Microsoft Teams Undefined Error (2026)
Struggling with Microsoft Teams 'Undefined Error' (2026)? Discover proven, step-by-step fixes like clearing cache, updating the app, and more. Get back to seamless collaboration fast!
People tend to use their computers longer than their other technological devices such as phones, tablets, etc. Therefore, it is advisable to regularly monitor and grasp the operating status of the device. Today's Chromebook models have a built-in application called "Diagnostic", which can help you perform periodic system checks extremely easily.
The Diagnostics app was first introduced in Chrome OS 90 in April 2020. It's a big upgrade from the previous system check method, which required users to access a rather complicated internal system page. It also comes with a bunch of useful tests that you can use to make sure all the system features are running smoothly.
How to open the Diagnostic app
You won't find Diagnostic in the launcher's app drawer like usual. However, there are two other ways to launch it. First, click the launcher icon (the circle) on the taskbar.

Tap on the search box and type in the keyword “Diagnostic”. Tap on the “Diagnostic” app when it appears in the corresponding search results.

For the second method, you'll open Diagnostic from Chrome OS Settings. First, click the clock icon on the taskbar to bring up the Quick Settings panel. Then, click the gear icon to open the Settings menu.

Next, click on “About Chrome OS” in the left sidebar.

Now, click on “Diagnostics” to launch the application.

Using Diagnostic
The Diagnostics app is basically divided into three sections: Battery, CPU, and Memory. Each section will give the user an overview of the relevant information, as well as instructions on how to perform the necessary checks. Specifically as follows.
The “Battery” section will show you the battery capacity of your device and how much more battery life you have left. Below that are three different metrics:

You'll also see the option to "Run Discharge Test" or "Run Charge Test," depending on whether your Chromebook is plugged in or not. These tests will measure how quickly your device is charging or discharging.

Next is the “CPU” section. Information about your device’s processor will be displayed at the top, and you can also see a real-time graph of CPU usage below. There are three metrics here:

For more information, click “Run CPU Test”. Several tests will be performed to ensure that the CPU is working properly.

The last section is “Memory”. The blue progress bar shows the amount of available memory (RAM) in real time. You can click “Run Memory Test” for some more details. This test will take about 15 minutes.

At the bottom of the page, you can click the “Save Session Log” button to read all the test data you have performed.

Struggling with Microsoft Teams 'Undefined Error' (2026)? Discover proven, step-by-step fixes like clearing cache, updating the app, and more. Get back to seamless collaboration fast!
Discover simple, step-by-step methods to disable Microsoft Teams at startup and unlock better PC performance. Faster boot times, less resource drain—perfect for Windows users seeking smooth operation.
Stuck with Microsoft Teams "Network Error" offline? Discover proven, step-by-step solutions to fix Microsoft Teams network error offline quickly. Get back online fast—no tech skills needed!
Struggling with Microsoft Teams Error 4oggx? Discover proven fixes to resolve sign-in failures, crashes, and connectivity issues fast. Get back to productive calls without frustration!
Encountering the frustrating Microsoft Teams "Remove Account" Data Error? Discover quick, reliable fixes like clearing cache, resetting the app, and more to get back to seamless collaboration without losing data. Updated with the latest solutions.
Tired of the frustrating Microsoft Teams "Layout Error" Sidebar? Follow our proven, step-by-step troubleshooting guide with the latest fixes to get your Teams sidebar working smoothly again. No tech skills needed!
Stuck with Microsoft Teams offline error in 2026? Discover proven troubleshooting steps, common causes, and quick fixes to restore your connection fast. No tech skills required!
Tired of Microsoft Teams crashing with "Error M" memory issues? Follow our step-by-step guide to fix Error M in Teams, clear cache, update software, and boost performance—no tech skills required!
Discover the easiest step-by-step guide to setting up Microsoft Teams Town Hall events. Host massive virtual gatherings effortlessly with pro tips for seamless execution. Perfect for leaders and organizers!
Struggling with Microsoft Teams "Download Error" on PC? Discover proven, step-by-step fixes to resolve download failed issues quickly. Get back to seamless collaboration in minutes—no tech skills needed!
Stuck with Microsoft Teams "Error L" License error? Follow this step-by-step troubleshooting guide to resolve licensing issues quickly, restore access, and boost productivity without IT hassle. Updated with latest fixes.
Tired of Microsoft Teams video call freezing mid-meeting? Follow this proven troubleshooting Microsoft Teams video call freezing guide with quick fixes, advanced tips, and real solutions to restore smooth video instantly.
Frustrated by Microsoft Teams 'Download Failed Due to Unexpected Error'? Discover proven, step-by-step solutions to fix this common issue quickly and get back to seamless collaboration. Updated with the latest fixes for peak performance.
Frustrated because your Microsoft Teams recording failed? Uncover the top common reasons like permissions issues, storage limits, and network glitches, plus step-by-step fixes to prevent future failures and record flawlessly every time.
Struggling with Microsoft Teams "Error B" connection? Discover step-by-step fixes for smooth connectivity. Clear cache, check networks, and more in this ultimate guide to resolving Error B instantly.