diff --git a/batch/packdat.bat b/batch/packdat.bat
index 8a50e11..73eba13 100644
--- a/batch/packdat.bat
+++ b/batch/packdat.bat
@@ -18,11 +18,15 @@ set "datpath=%~dp1"
 if "%~2" == "" (
     set "datfile=%~nx1.dat"
 ) else (
-    set "datfile=%~nx2"
+    set "datfile=%~nx2.dat"
 )
 
 del "%~dp1%datfile%.bak" 2>nul
 ren "%~dp1%datfile%" "%datfile%.bak" 2>nul
 cd /d "%~dpnx1"
-dat2.exe a -r "..\%datfile%" *
+if exist "%retdir%\dat2.exe" (
+    "%retdir%\dat2.exe" a -r "..\%datfile%" *
+) else (
+    dat2.exe a -r "..\%datfile%" *
+)
 cd /d "%retdir%"