diff --git a/libvm/as/Makefile b/libvm/as/Makefile
index 19cee5f..4f39397 100644
--- a/libvm/as/Makefile
+++ b/libvm/as/Makefile
@@ -1,8 +1,3 @@
-
-
-
-
-
 all: as
 
 as: as.c tokens.c ../mnemonics.c ../disassembler.c
diff --git a/libvm/as/as.c b/libvm/as/as.c
index 3c98c72..e8726f0 100644
--- a/libvm/as/as.c
+++ b/libvm/as/as.c
@@ -1,17 +1,22 @@
 
+#include "tokens.h"
+#include "../vm.h"
+#include "../mnemonics.h"
+#include "../disassembler.h"
+
 #include <stdbool.h>
 #include <stdio.h>
-#include <getopt.h>
 #include <stdlib.h>
 #include <stdint.h>
 #include <ctype.h>
 #include <string.h>
 #include <stdarg.h>
 
-#include "tokens.h"
-#include "../vm.h"
-#include "../mnemonics.h"
-#include "../disassembler.h"
+#if defined(_MSC_VER)
+#include "../getopt.h"
+#else
+#include <getopt.h>
+#endif
 
 struct llist
 {
@@ -251,7 +256,7 @@ int main(int argc, char **argv)
 			}
 			listing = fopen(optarg, "w");
 			if(listing == NULL) {
-				fprintf(stderr, "Could not open %s.\n");
+				fprintf(stderr, "Could not open %s.\n", optarg);
 				exit(1);
 			}
 		}
@@ -347,7 +352,7 @@ void apply_modifier(instruction_t *i, const char *mod)
 
 	if(strncmp("cmd:", mod, 4) == 0)
 	{
-		fprintf(stderr, "Command specification %s not supported yet.\n");
+		fprintf(stderr, "Command specification %s not supported yet.\n", mod);
 		exit(1);
 	}
 	
diff --git a/libvm/build.bat b/libvm/build.bat
index ac3f703..2142dc2 100644
--- a/libvm/build.bat
+++ b/libvm/build.bat
@@ -15,6 +15,9 @@ echo Building emulator...
 SET LIBS= /NXCOMPAT /DYNAMICBASE "SDL.lib" "kernel32.lib" "user32.lib" "gdi32.lib" "winspool.lib" "comdlg32.lib" "advapi32.lib" "shell32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /DEBUG /MACHINE:X64 /OPT:REF /INCREMENTAL:NO /SUBSYSTEM:CONSOLE /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /OPT:ICF /ERRORREPORT:PROMPT /NOLOGO /TLBID:1 /NODEFAULTLIB:msvcrt.lib
 cl %INIT% /I "SDL-1.2.15\include" emulator.c vm.c getopt.c %OPTIONS% /link %LIBS%
 
+echo Building assembler...
+cl %INIT% /DYY_NO_UNISTD_H as\as.c as\tokens.c mnemonics.c disassembler.c getopt.c %OPTIONS%
+
 echo Cleaning up...
 del *.obj
 SET PATH=%PATHSAVE%