If one of these resolves your problem, close the app and continue working. Use the Microsoft 365 shared computer activation (SCA) troubleshooter to enable shared computer activation for Microsoft 365 applications. If your account is locked due to multiple unsuccessful login attempts, wait for the lockout period to end.

Common Causes of Office 365 Sign-In and Activation Issues

Use the Microsoft 365 activation troubleshooter to resolve Microsoft 365 subscription activation issues. Slow performance can be due to heavy CPU usage or low available memory. Close unused tabs, background processes, or applications to free up system resources. Additionally, ensure you’ve installed all available updates, as performance improvements are often included in patches.

I can't sign in to my Microsoft account

In this comprehensive guide—KB113—we’ll explore the most common causes of Office 365 sign-in and activation issues. We’ll then walk you through a practical, step-by-step troubleshooting methodology. Combine these best practices with ongoing training and proactive license management, and you’ll be well on your way to a stable, secure Office 365 environment. Sometimes, an expired license or outdated credentials are the culprit. Other times, it might be network problems, conflicting versions of Office, or organizational security policies that block the authentication process.

What should I do if updates for Microsoft 365 apps fail to install?

Follow this guide to ensure a smooth and error-free Microsoft 365 login experience. Additionally, check out the above-listed security best practices and keep your team members aware of common troubleshooting tips. Troubleshooting Microsoft 365 login issues often requires a methodical approach, starting with basic checks and escalating to more complex troubleshooting if needed. Remember, proactive management and regular reviews of your IT infrastructure can prevent many common issues, keeping your business operations running smoothly. Make sure your phone’s operating system is supported by Microsoft 365.

Frequently asked questions

If you can't sign into your Microsoft account, most issues can be identified by our sign-in helper tool. If you encounter this error – Sorry, we are having temporary server issues, then chances are that the issue lies at Microsoft’s end. Alternatively, you can use the browser’s incognito mode or private mode to check if the issue persists. If you would like to ask me another question in the future, you can add me as a favorite Expert. You'll have the option to do that on your \"My Questions\" page if you choose to rate our interaction or you can request me by name if you wish. You'll FixTechGuide Office 365 troubleshooting have the option to do that on your "My Questions" page if you choose to rate our interaction or you can request me by name if you wish.

• Clearing cached credentials, running a repair, or using the Microsoft Support and Recovery Assistant (SaRA) can also address common local device issues.
• Use the Microsoft 365 network connectivity test to measure connectivity between your device and the internet, and from there to Microsoft’s network.
• In this guide, we will take an in-depth look at troubleshooting and resolving common Microsoft 365 login problems so you can keep your business running smoothly.
• Start with the very basic checks and move to the more complex troubleshooting tips.
• Make sure your phone’s operating system is supported by Microsoft 365.
• Use the Microsoft 365 setup troubleshooter to install Microsoft 365, Office 2021, Office 2019, or Office 2016 on your Windows PC.
• Verify that you’re logged into the correct Microsoft account both in OneDrive and Office apps.

If a troubleshooter is available for your issue, select Start to run that troubleshooter. You might find it simple, but the most resolve Outlook not sending emails fast common cause of login failure is entering the wrong username and password combinations. Below is a structured approach to diagnosing and resolving Office 365 sign-in or activation errors.



Sometimes cached credentials on your device or a corrupted Office profile can lead to repeated sign-in prompts or activation failures. Office 365 uses several internet endpoints and cloud services to authenticate users and validate licenses. If these connections are disrupted, sign-in and activation will fail. Use the Excel check troubleshooter to resolve Excel for Windows startup, hang, or crash issues. Get Help has troubleshooters for Microsoft 365 you can run for many common scenarios. These often help resolve issues without the need to contact support.





If you’re unable to sign in to your Microsoft 365 account, ensure you’re using the correct email and password. Locked accounts, due to multiple failed attempts, may require waiting or following unlock instructions. Check your internet connection, as weak connectivity can cause issues. For work or school accounts, confirm with your organization that your account is active.

Enable permissions for file access and notifications within app settings. For syncing repair PST file without data loss or email issues, verify your mobile connection or switch between WiFi and cellular data. Reinstall the app if problems persist using Microsoft’s compatibility manuals. Larger files may cause a temporary slowdown, so ensure your device has adequate memory.