If your account is locked due to multiple unsuccessful login attempts, wait for the lockout period to end. It can vary from 1 to 30 minutes, depending on the number how to fix Outlook not opening today of failed attempts you have performed. Once the waiting period is over, try logging in again with the right credentials. In these scenarios, you’ll need more in-depth knowledge of Office 365 licensing, Azure Active Directory (Azure AD) configurations, or advanced policy settings.

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 Fix Outlook and Office 365 Errors 2025 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 Sometimes, an expired license or outdated credentials are the culprit.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

The Microsoft Support and Recovery Assistant can automate fixes for common error codes. The "Unlicensed Product" error usually indicates an inactive or unlinked subscription. Confirm your subscription status and sign in with the correct Microsoft account. Run the Activation Troubleshooter, accessible online or via your app settings.

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.
• Use the uninstall troubleshooter to uninstall Microsoft 365, Office 2021, Office 2019, or Office 2016 from your Windows PC.
• 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.
• Other times, it might be network problems, conflicting versions of Office, or organizational security policies that block the authentication process.
• Look up the error code on the official Microsoft site for tailored steps.

You might find it simple, but the most 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. Start with the basics and move toward more advanced methods only if necessary.

Microsoft 365 Troubleshooting – Quick Fixes for Common Problems

Understanding these root causes will help you map out a clearer resolution path. In many cases, performing simple checks—like verifying correct usernames and valid licensing—will resolve the issue quickly. After you run any troubleshooter, Get Help provides details on any findings and suggestions for possible remedies. connection status shows disconnected 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.