diff --git a/commands/core/archive.drush.inc b/commands/core/archive.drush.inc
index a7cb4e8..ecf914d 100644
--- a/commands/core/archive.drush.inc
+++ b/commands/core/archive.drush.inc
@@ -170,6 +170,12 @@ function drush_archive_dump($sites_subdirs = '@self') {
   $docroot = basename($docroot_path);
   $workdir = dirname($docroot_path);
   $dereference = (drush_get_option('preserve-symlinks', FALSE)) ? '' : '--dereference ';
+  // Convert destination path to Unix style for tar on MinGW - see http://drupal.org/node/1844224
+  if (drush_is_mingw()) {
+    $destination_orig = $destination;
+    $destination = str_replace('\\', '/', $destination);
+    $destination = preg_replace('$^([a-zA-Z]):$', '/$1', $destination);
+  }
   // Archive Drupal core, excluding sites dir.
   drush_shell_cd_and_exec($workdir, "$tar {$tar_extra_options} --exclude \"{$docroot}/sites\" {$dereference}-cf %s %s", $destination, $docroot);
   // Add sites/all to the same archive.
@@ -257,6 +263,11 @@ function drush_archive_dump($sites_subdirs = '@self') {
     drush_shell_cd_and_exec($workdir, "$tar --dereference -vrf %s %s", $destination, $docroot . '/sites/default/default.settings.php');
   }
 
+  // Switch back to original destination in case it was modified for tar on MinGW.
+  if (!empty($destination_orig)) {
+    $destination = $destination_orig;
+  }
+
   // Compress the archive
   drush_shell_exec("gzip --no-name -f %s", $destination);
 
diff --git a/drush b/drush
index 323fc6f..0e86d14 100755
--- a/drush
+++ b/drush
@@ -11,6 +11,14 @@
 SELF_DIRNAME="`dirname -- "$0"`"
 SELF_PATH="`cd -P -- "$SELF_DIRNAME" && pwd -P`/`basename -- "$0"`"
 
+# Decide if we are running a Unix shell on Windows
+case "`uname -a`" in
+  CYGWIN*)
+    CYGWIN=1 ;;
+  MINGW*)
+    MINGW=1 ;;
+esac
+
 # Resolve symlinks - this is the equivalent of "readlink -f", but also works with non-standard OS X readlink.
 while [ -h "$SELF_PATH" ]; do
     # 1) cd to directory of the symlink
@@ -25,10 +33,9 @@ done
 
 # Build the path to drush.php.
 SCRIPT_PATH="`dirname "$SELF_PATH"`/drush.php"
-case "`uname -a`" in
-  CYGWIN*)
-    SCRIPT_PATH="`cygpath -w -a -- "$SCRIPT_PATH"`" ;;
-esac
+if [ ! -z "$CYGWIN" ] ; then
+  SCRIPT_PATH="`cygpath -w -a -- "$SCRIPT_PATH"`"
+fi
 
 # If not exported, try to determine and export the number of columns.
 # We do not want to run `tput cols` if $TERM is empty or "dumb", because
@@ -37,7 +44,8 @@ esac
 # error message is suppressed, but tput cols becomes confused about the
 # terminal and prints out the default value (80).
 if [ -z $COLUMNS ] && [ -n "$TERM" ] && [ "$TERM" != dumb ] && [ ! -z "`which tput`" ] ; then
-  # Note to cygwin users: install the ncurses package to get tput command.
+  # Note to cygwin/mingw/msys users: install the ncurses package to get tput command.
+  # Note to mingw/msys users: there is no precompiled ncurses package.
   if COLUMNS="`tput cols`"; then
     export COLUMNS
   fi
@@ -58,8 +66,7 @@ else
   fi
 
   # On MSYSGIT, we need to use "php", not the full path to php
-  # See http://drupal.org/node/1659014 for an explanation of the comparison op.
-  if [ ! -z "$MSYSTEM" ] && [ "x${MSYSTEM}" != "x${MSYSTEM#MINGW}" ] ; then
+  if [ ! -z "$MINGW" ] ; then
     php="php"
   fi
 fi
@@ -67,6 +74,13 @@ fi
 # Check to see if the user has provided a php.ini file or drush.ini file in any conf dir
 # Last found wins, so search in reverse priority order
 for conf_dir in "`dirname "$SELF_PATH"`" /etc/drush $HOME/.drush ; do
+  if [ ! -d $conf_dir ] ; then
+    continue
+  fi
+  # Handle paths that don't start with a drive letter on MinGW shell. Equivalent to cygpath on Cygwin.
+  if [ ! -z "$MINGW" ] ; then
+    conf_dir=`sh -c "cd $conf_dir; pwd -W"`
+  fi
   if [ -f "$conf_dir/php.ini" ] ; then
     drush_php_ini=$conf_dir/php.ini
   fi
diff --git a/includes/drush.inc b/includes/drush.inc
index 13535f6..9ae2fc1 100644
--- a/includes/drush.inc
+++ b/includes/drush.inc
@@ -926,7 +926,7 @@ function drush_download_file($url, $destination = FALSE, $cache_duration = 0) {
 function _drush_download_file($url, $destination, $overwrite = TRUE) {
   static $use_wget;
   if ($use_wget === NULL) {
-    $use_wget = drush_shell_exec('which wget');
+    $use_wget = drush_shell_exec('wget --version');
   }
 
   $destination_tmp = drush_tempnam('download_file');
diff --git a/includes/environment.inc b/includes/environment.inc
index 4f2ae73..52e9504 100644
--- a/includes/environment.inc
+++ b/includes/environment.inc
@@ -644,14 +644,16 @@ function drush_is_mingw($os = NULL) {
  * Return tar executable name specific for the current OS
  */
 function drush_get_tar_executable() {
-  return drush_is_windows() ? "bsdtar.exe" : "tar";
+  return drush_is_windows() ? (drush_is_mingw() ? "tar.exe" : "bsdtar.exe") : "tar";
 }
 
 /**
  * Checks if the operating system has bash.
+ *
+ * MinGW has bash, but PHP isn't part of MinGW and hence doesn't run in bash.
  */
 function drush_has_bash($os = NULL) {
-  return drush_is_cygwin($os) || !drush_is_windows($os);
+  return (drush_is_cygwin($os) && !drush_is_mingw($os)) || !drush_is_windows($os);
 }
 
 /*