Yeelight color E27 bulb not accessible from certain ISP

Dear Yeelight forum members,

i am in possession of a Yeelight color bulb (E27) and I am having difficulties connecting to it. It connects to my home network but it apparently fails to connect to the Yeelight servers which makes me unable to control the lightbulb (it displays the following error message: “connection timed out”). My home network is from the Dutch ISP called ‘KPN’. KPN support staff was unable to resolve the issue. I have tried connecting the bulb to a hotspot set up by my smartphone, the smartphone uses a different ISP called Vodafone. The bulb managed to connect to the Yeelight servers via the Vodafone ISP which allowed me to control it but not trough the KPN ISP. Can you help me finding the source of the problem?

In short:

  • I try to connect the bulb in the Yeelight app.
  • It fails and displays the following message: “connection timed out”.
  • Bulb is connected to my home network but I cannot see it in the app and I cannot control the bulb.
  • Under Vodafone ISP, the app succeeds in connecting and I can control the bulb.

I think your problem is clear now, it is the issue blocked by KPN ISP. could you try to ping “” to see if it’s reachable. If it failed, you should ask KPN for support to reach ‘’ for you.