Hi Ian,
this error means it was unable to load data from the ogimet site. I just checked the source and it works, however the ogimet page has always been very slow and I think it is getting slower and slower and question is how much slower it can get before it is unusable. At times Ive seen response times of over 20 seconds even when you go directly to ogimet.com and look from there.
I would hope this was only a temporary glitch. Is it still not working now?