However, if the administrator is unable to resolve issues with the help of self-service support resources, they should Contact support. Technical support for Microsoft 365 operated by 21Vianet subscriptions provides assistance with basic installation, setup, and general technical usage. If you’re a volume licensing admin but are unable to access the admin center, you can create an online support request. With every subscription of Microsoft 365 operated by 21Vianet, 21Vianet support provides technical, presales, billing, and subscription support. Have your Microsoft 365 apps suddenly started crashing after a recent Windows or Office update? Many users experience random application freezes, launch errors, and constant crashes after installing new patches or cumulative updates.

⃣ Reset Browser Cookies & Cache

21Vianet understands that receiving timely technical support from qualified professionals is a key aspect of cloud services. Equally important is the critical role that the customer’s IT department plays in the support of its users. The Microsoft 365 operated by 21Vianet technical support team troubleshoots only those issues that are related to Microsoft 365 operated by 21Vianet. Incorrect system time can break your connection to Microsoft’s authentication servers. Always enable Set time automatically and select the correct region in your Windows settings.

Microsoft 365 Apps Crashing After Update — Step-by-Step Repair Guide

• If login issues are still persisting, our experts can assist you live via WhatsApp.
• When Office 365 search stops working after updates, it’s usually a minor indexing or cache issue — not a major fault.
• Stay tuned on FixTechGuide.com for more troubleshooting guides and expert fixes.
• Then open any Office app → File → Account → Update Options → Update Now to ensure both are synchronized.
• 2 Severity A is only available to customers who signed an advanced online service agreement with 21Vianet through a sales account manager.
• The Microsoft 365 Copilot app empowers your employees to do their best work with Copilot in the apps they use daily.
• Outlook and Office 365 sync issues can be frustrating but are almost always fixable.
• Download the tool from Microsoft and run the Outlook diagnostic to auto-detect server and account issues.

For iPhone users, reinstalling Outlook or updating to the latest iOS often resolves stuck sign-in loops instantly. Many users have both personal Microsoft accounts (e.g., Exchange connectivity diagnostic Outlook.com) and work/school Office 365 accounts. If both are signed in simultaneously, the system can confuse the authentication path.

? Fix Office 365 Login Issues on Mobile

21Vianet assigns a severity level to a case when it’s opened, based on an assessment of the issue type and customer impact. Examples of issue types and severity levels are shown in the following table. Authorized administrators can use the Microsoft 365 operated Repair PST File Without Data Loss by 21Vianet portal to submit service requests online and access support telephone numbers.

Step 2 – Update Outlook and Office 365

We provide instant guidance for update errors, installation failures, Fix Outlook and Office365 Sync Issues and Office activation issues. When Office 365 search stops working after updates, it’s usually a minor indexing or cache issue — not a major fault. Following the steps above should restore your search functionality quickly. For advanced troubleshooting, FixTechGuide offers remote support to restore performance and indexing accuracy for Outlook and other Office apps. Microsoft 365 crashes after updates can be frustrating, but these fixes will restore stability quickly.





Microsoft 365 with Microsoft Teams helps deliver a complete, secure solution to help everyone work better, smarter, and more cohesively. Microsoft Create has professionally designed, fully customizable templates to help you get things done. Find solutions to common problems or get help from a support agent.