That's what pops up in the console every few minutes and on startup. Been happening for months. The world Pigtopia has a WorldBorder at ±5000 and the chunks beyond that have been trimmed multiple times to no avail. What could be causing this?
HappyPikachu Try extending the Border of the world, and find the so called horse or coordinates of the location, do a //regen, then trim the border again.
HelpfulBeast Finally got around to it (yes, 2 months later xD), didn't work unfortunately. New terrain, no horse there. Any other ideas?
"That horse IS in the wrong location, Pigtopia is only for pigs!" Sorry, that was the first thing that popped into my head. Try posting your plugins list for the off-chance a plugin could be creating a glitched entity. The horse could be teleported there, or something might be pushing it. There is also a chance that someone/something wrongly edited its NBT data causing it to glitch out.
look at the error again... its yelling about a mismatch in storage. if you have a mca editor remove the entity entry from the r.0.-1.mca file? (chunk 5,-8 is close to map center infact) ya try even teleporting it? look like it has a entity number of 732?
I would use NBTExplorer to find the phantom horse and delete it. Chunk 5,-8 is in r.0.-1.mca I always have trouble finding the relative chunk location in the file, especially with negative numbers. But r.0.-1.mca contains chunks 0,-32 to 31,-1, maybe that's 5,24 within the file. Whatever you do, make a backup first! Oh, and only edit .mca files when the server is shut down.
I still cant get why when looking from a top down design of mapping they went with Y as the height variable that always still gets me. But yeah when you see that kind of error thats a chunk storage issue saying hey Im said to be 'over here' but Im stored 'here' in this mapping file. Just a matter of figureing out the proper mca file to fix its easy when its very close to middle of the map. http://minecraft.gamepedia.com/Region_file_format shows the formula for calulating the proper file if you know the chunk grid.
Thanks for the responses! We had HorseKeep for a while, wasn't the best plugin. It has since been removed. So, think I'm going to try NBTExplorer. Will post results!