Use the Microsoft 365 network connectivity test to measure connectivity between your device and the internet, and from there to Microsoft’s network. Use the MIcrosoft 365 inventory scan troubleshooter to generate either a normal repair corrupted OST in Outlook or full scan report of your computer and installed Microsoft 365 applications. Use the Microsoft 365 sign-in troubleshooter to help resolve sign-in issues encountered with Microsoft 365. If you can't sign into your Microsoft account, most issues can be identified by our sign-in helper tool.

How do I fix the ‘Product Activation Failed’ error in Microsoft 365?

Always verify offline availability settings for critical documents you might need. In this comprehensive guide—KB113—we’ll Office 365 Sync Errors Fix 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 Sometimes, an expired license or outdated credentials are the culprit.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.

Recover your account

If the issue persists, Microsoft has created a dedicated tool called Microsoft Support and Recovery Assistant (SaRA) to automate many troubleshooting tasks. The tool will ask you to enter the email address or mobile phone number you're trying to sign in with and check the details you provide. If we detect a problem with your account, we'll tell you what you need to do to solve the problem.

3 Step 3: Verify Network Connectivity and Firewall Settings

• Use the Microsoft 365 network connectivity test to measure connectivity between your device and the internet, and from there to Microsoft’s network.
• Yes, Microsoft 365 works offline for most apps like Word and Excel.
• If syncing is paused, resume it from the OneDrive system tray icon.
• Open apps in Safe Mode to bypass add-ins and check for improvements.
• Look up the error code on the official Microsoft site for tailored steps.
• You can feel free to contact our experts, as they are available 24X7 for solving your issues.

If you are using an outdated web browser or Office app, it can create compatibility issues, which eventually lead to Microsoft 365 sign-in problems. Make sure to update them to the latest version and try again to fix Microsoft 365 login issues. If you are still unsure about the right password and are facing Microsoft 365 login issues, use the Forgot Password option to reset your password.

Microsoft 365 Troubleshooting – Quick Fixes for Common Problems

Use the Microsoft 365 activation troubleshooter to resolve Microsoft 365 subscription activation issues. Slow performance expert Outlook tips by FixTechGuide can be due to heavy CPU usage or low available memory. Close unused tabs, background processes, or applications to free up system resources.