diff --git a/CPP/myWindows/mySplitCommandLine.cpp b/CPP/myWindows/mySplitCommandLine.cpp
index f8b99b8..7d762bc 100644
--- a/CPP/myWindows/mySplitCommandLine.cpp
+++ b/CPP/myWindows/mySplitCommandLine.cpp
@@ -105,12 +105,8 @@ static void GetCpuName(AString &s)
 void mySplitCommandLine(int numArguments, char *arguments[],UStringVector &parts) {
 
   { // define P7ZIP_HOME_DIR
-    static char p7zip_home_dir[MAX_PATH];
-    AString dir,name;
-    my_windows_split_path(arguments[0],dir,name);
-    snprintf(p7zip_home_dir,sizeof(p7zip_home_dir),"P7ZIP_HOME_DIR=%s/",(const char *)dir);
-    p7zip_home_dir[sizeof(p7zip_home_dir)-1] = 0;
-    putenv(p7zip_home_dir);
+    if(getenv("P7ZIP_HOME_DIR") == NULL)
+       putenv("P7ZIP_HOME_DIR=" P7ZIP_HOME_DIR);
   }
 
 #ifdef ENV_HAVE_LOCALE