Author: TomH
[Added to the original trac issue at 11.26pm, Friday, 21st September 2012]

It's pretty much impossible to get that tile now isn't it? OpenLayers 2.12 won't let you zoom out far enough to trigger it...

I guess it might still happen when there's a network problem or something, but it's certainly not going to happen very often.

Author: don-vip
[Added to the original trac issue at 11.33pm, Friday, 21st September 2012]

I see it every day at work, but this is one of the many bugs caused by our annoying enterprise proxy. By the way, I don't understand the message, as in my case, more OSM will never come :)

Author: TomH
[Added to the original trac issue at 11.38pm, Friday, 21st September 2012]

I've updated the image now anyway - it should deploy shortly.

Author: dneelyep[at]gmail.com
[Added to the original trac issue at 11.40pm, Friday, 21st September 2012]

In case it helps diagnose anything, the tile displayed for me while zoomed in at maximum zoom level, at http://www.openstreetmap.org/?lat=38.2089418172836&lon=-85.7554391026497&zoom=18
Unfortunately I've closed the tab that displayed the error, so I don't have a screenshot to include.

And great, many thanks TomH.