Index: src/OFStreamSocket.m
==================================================================
--- src/OFStreamSocket.m
+++ src/OFStreamSocket.m
@@ -71,11 +71,15 @@
 	if (eos) {
 		OFReadFailedException *e;
 
 		e = [OFReadFailedException newWithClass: isa
 					  requestedSize: size];
+#ifndef _WIN32
 		e->errNo = ENOTCONN;
+#else
+		e->errNo = WSAENOTCONN;
+#endif
 
 		@throw e;
 	}
 
 	if ((ret = recv(sock, buf, size, 0)) < 0)
@@ -99,11 +103,15 @@
 	if (eos) {
 		OFWriteFailedException *e;
 
 		e = [OFWriteFailedException newWithClass: isa
 					   requestedSize: size];
+#ifndef _WIN32
 		e->errNo = ENOTCONN;
+#else
+		e->errNo = WSAENOTCONN;
+#endif
 
 		@throw e;
 	}
 
 	if ((ret = send(sock, buf, size, 0)) == -1)