Tally ERP unable to activate after tailscale installation

In india Tally ERP (tallysolutions.com) is one of the famous accounting software used in small & medium business, almost 80% business in india uses tally, we have found that after installing tailscale where tally is installed, tally unable to activate the license and if we uninstall tailscale it works.

Below are a few details:

  1. Tally uses TCP/UDP port 9999 for it’s license server module, every tally instance communicates with the license server on port 9999 even localhost, to verify it’s license validity.

Let me know if you need any further details to troubleshoot the issue, as we have tried tailscale on 5+ different clients locations where tally is installed, the issue remains the same. once tailscale is un-installed it works.

does anybody faced similar issus.

Weird. We don’t modify the routes for localhost.

What’s the Tailscale IP of a machine where this happened, and the approximate date/time? We’ll try and look to see if it’s obvious what happened.

If you can reproduce this, though, then I’m sure it’s easy for us to fix.