diff --git a/forge-1.16.5/src/main/java/org/dynmap/forge_1_16_5/DynmapPlugin.java b/forge-1.16.5/src/main/java/org/dynmap/forge_1_16_5/DynmapPlugin.java
index 906d05a4..29104fe4 100644
--- a/forge-1.16.5/src/main/java/org/dynmap/forge_1_16_5/DynmapPlugin.java
+++ b/forge-1.16.5/src/main/java/org/dynmap/forge_1_16_5/DynmapPlugin.java
@@ -1823,6 +1823,7 @@ public class DynmapPlugin
         	if(!onblockchange) return;
         	BlockUpdateRec r = new BlockUpdateRec();
         	r.w = event.getWorld();
+            if(!(r.w instanceof ServerWorld)) return;  // band-aid to prevent errors in unsupported 'running in client' scenario
 			ForgeWorld fw = getWorld((IServerWorld)r.w, false);
 			if (fw == null) return;
 			r.wid = fw.getName();