Why is My QuickBooks multi user mode not working after Windows updates? 1-855-409-2300 QuickBooks multi-user mode not working after Windows updates due to several reasons. Windows updates can alter network settings, firewall configurations, and user permissions, disrupting QuickBooks' ability to communicate over a network. Additionally, these updates might conflict with QuickBooks' database server manager or affect the QuickBooks application itself. Common issues include: 1. Firewall and Antivirus Settings: Updates can reset or alter these settings, blocking the ports QuickBooks uses. 2. Network Configuration: Changes in network settings or IP addresses can disrupt communication between the server and workstations. 3. Permissions: Updates might change file or folder permissions, preventing access to necessary files. 4. Service Interruption: QuickBooks Database Server Manager service might be stopped or disabled during the update. To resolve these issues, reconfigure the firewall, check network settings, ensure proper permissions, and restart the QuickBooks Database Server Manager service.