[Grimm_Wolfe]

Okay, I'm missing some information. Who owns the claim? You or the other player? If you're building on land under another player's claim (either protected or built upon prior), they may ask you to leave under the trespassing clause of miscellaneous rules section; it's also under the the server's /rules.

Was there some building agreement where this player allowed you to build on their land? Or do you both co-own the land?