Bad block causing client crash

[Steel Fox]

I have a server running horizons 1.0.9. Last night I was trying to build an arena to fight the Ars Magica air guardian near my base and I put down a gold inlay on top of a marble paver and I guess that was a bad idea. It created some sort of unloadable block. Any time I am within render distance of that block my client crashes. Server seems to be fine. Keeps chugging away. As a result I can't get anywhere near my base.

Any ideas on how I can fix this? Attached is the crash report log.

 

[Steel Fox]

Well I got it fixed. I downloaded MCedit. I had to do a bit of folder gymnastics to get it to work with my server because MCedit doesn't let you choose the working folder.
Just in case someone else needs to do this as well in the future:
In order for MCedit to work you need the world folder in C:\users\profile name\app data\roaming\.minecraft\saves\
Windows won't let you make a folder called .minecraft in the normal way to get around this
I installed the vanilla minecraft client (not the server version) on my server and ran it to generate the needed folders.
I then made a copy of my server folder and renamed that to saves then copied it into the .minecraft folder.
MCedit recognized my world as a save and let me begin editing.
Since I already knew where the problem was in my world I simply deleted the offending block and a few blocks around it for good measure.
I then copied the folder back to where I keep my server files. Renamed the old copy to .bak and Renamed the fixed version to what it was before.
Then I could run the server as normal. All my modded blocks are still as they were and the no-mans-land is now fixed.