The QuickBooks error H202 occurs thanks to server connection error, which denies establishing the multi-user connection mode. Fixing this error would require you to download and install the QuickBooks tool hub on your computer then open it and navigate to the network issues. Now choose QuickBooks database server manager, now within this feature select start scan, further the database server manager will repair the firewall permissions manually, now click close. you'll now open the QuickBooks on multiple workstations and attend file and switch to multi-user mode. After following the steps, you'll be ready to fix the error H202 within the QuickBooks application.