diff --git a/src/server.py b/src/server.py
--- a/src/server.py
+++ b/src/server.py
@@ -123,11 +123,13 @@ class Server(NetNode):
 		log.info("received request for data block #{0}".format(index))
 
 		jsonResponse={"command":"send", "index":index, "dataType":"data"}
-		if self._lastIndex+1!=index:
-			self._dataFile.seek(index*self.BLOCK_SIZE)
-		binResponse=self._dataFile.read(self.BLOCK_SIZE)
+		blocks=[]
+		for i in index:
+			if self._lastIndex+1!=i:
+				self._dataFile.seek(i*self.BLOCK_SIZE)
+			blocks.append(self._dataFile.read(self.BLOCK_SIZE))
 
-		return (jsonResponse,binResponse)
+		return (jsonResponse,b"".join(blocks))
 
 	def _receiveData(self,jsonData,binData):
 		if not self.isLocked(): self._lock()