Suddenly, No IP Connection

My setup has been working fine for years.

This morning, I turned on my machine and booted up Lightburn.

I sent a job to the laser and got the “Transfer failed” message in Lightburn (1.6.00). Ruida 6445G mainboard version RDC-V15.1.18.

  1. I checked the IP settings on the Ruida controller and Lightburn. Identical.

  2. I did a reset on the Ruida controller. I unplugged and replugged both the cable and the power. (I swabbed out the cable connector on the machine.)

  3. I checked my cable with a tester - all good, signal hitting on all 8 wires.

  4. I pinged the Ruida controller . . . Request timed out.

In the bottom right of the Ruida screen, there are two little computer monitors, one overlapping the other. When I turn on the machine, there is a little red “x” next to those monitors, but when the controller completes power-on cycle, the red “x” disappears.

Any other ideas? Controller failure?

Is your Ethernet cable plugged directly into the Ruida controller, or through some kind of extension cable from the controller to the outside of the machine? If an extension, try plugging directly into the controller. Are there any other devices on your network, or just your laser and your computer? If other devices, can you ping anything else on the network?

Thanks. The Ruida controller has a “harness” connected internally to the red-and-black laser . . . there is no ethernet port on the Ruida itself. It is plugged in “directly.” The rest of the network pings just fine.


I did an “ipconfig” and noticed an “Avast Secureline VPN Media disconnected.”

I went to Network Settings, disabled the Avast Secureline VPN network adapter . . . and then proceeded to delete any and every vestige of Avast that I could find: files, folders, task manager, etc.

Once I had cleaned all that out and rebooted my machine, things were back to normal.

AVAST appears to be a rather PERNICIOUS program. Once upon a time, I had been using Avast, but was pretty sure that I had wiped it clean. Occasionally, I have found that it reappears mysteriously on my machine – and it ALWAYS causes problems.

Anyway, for the time being, I’m satisfied that I am cutting again . . . but I will be on the lookout for Avast if it ever rears its ugly head again.

1 Like

Glad you figured it out. Some of the antivirus stuff can do some pretty nasty stuff in the name of attempting to keep you safe. Working in IT for many years, I’ve seen a lot, and choose to not run any on my machines. Too resource intensive and tries to do dumb things in the background like you saw.

Well . . . the Solution was NOT a solution. I thought clearing out Avast is what did it, because I was able to run some successful cuts. But then I turned off the controller and laser for dinner. When I came back and turned it back on, it’s back to no connection, no ping.


I guess I can try reassigning a new IP address . . .

Okay, take 4. I changed the IP address on the Ruida controller . . . and then edited the IP address in Lightburn.

Now, it’s working again.

Fingers crossed. Perhaps something was automatically assigning IP address when Laser cutter was off.

If you connect to a simple router you have or like this cheap ones
you can configure a reduced DHCP pool and assign a fixed IP in the range but outside of the pool and you get always the same IP to your RUIDA.

1 Like