Control Panel - start, stop, and open your local billing app
Try these in order:
freegstbill:// - click Allow.Start FreeGSTBill.bat directly. A small black window should appear briefly.Install FreeGSTBill.bat first.data\port.txt in Notepad to see which port the app picked, or delete that file and restart to let the server pick a fresh one.Tip: Press F12 to open browser developer tools and check the Console tab for any errors. Share what you see if you ask for support.