I added this device a while ago but every time I open the GUI this window is still there.

I'm not sure how to get rid of it

Reboot and it will go away. It’s a bug from one of later releases.

I've been having a similar error for at least a month. Plus other anomalies about a couple of devices not communicating (that had been working for years).

I just rebooted my EISY and it installed v6.0.5. The problems seem to have gone away.

I had to clear Java cache and download a new copy of start.jnlp to get admin console working again.

Good luck.

I just added a new device and continue to get the same message, and I am on v6.0.5. Rebooting is the primary solution...being on 6.0.5 does not solve this problem.