diff --git a/src/calibre/ebooks/lrf/pdf/convert_from.py b/src/calibre/ebooks/lrf/pdf/convert_from.py
index ade9c0368b..0419244fa7 100644
--- a/src/calibre/ebooks/lrf/pdf/convert_from.py
+++ b/src/calibre/ebooks/lrf/pdf/convert_from.py
@@ -3,6 +3,7 @@ __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
 ''''''
 
 import sys, os, subprocess, logging
+from functools import partial
 from calibre import isosx, setup_cli_handlers, filename_to_utf8, iswindows
 from calibre.ebooks import ConversionError
 from calibre.ptempfile import PersistentTemporaryDirectory
@@ -10,10 +11,13 @@ from calibre.ebooks.lrf import option_parser as lrf_option_parser
 from calibre.ebooks.lrf.html.convert_from import process_file as html_process_file
 
 PDFTOHTML = 'pdftohtml'
+popen = subprocess.Popen
 if isosx and hasattr(sys, 'frameworks_dir'):
     PDFTOHTML = os.path.join(getattr(sys, 'frameworks_dir'), PDFTOHTML)
 if iswindows and hasattr(sys, 'frozen'):
         PDFTOHTML = os.path.join(os.path.dirname(sys.executable), 'pdftohtml.exe')
+        popen = partial(subprocess.Popen, creationflags=0x08) # CREATE_NO_WINDOW=0x08 so that no ugly console is popped up
+
 
 def generate_html(pathtopdf, logger):
     '''
@@ -25,13 +29,12 @@ def generate_html(pathtopdf, logger):
     tdir = PersistentTemporaryDirectory('pdftohtml')
     index = os.path.join(tdir, 'index.html')
     # This is neccessary as pdftohtml doesn't always (linux) respect absolute paths
-    cmd = PDFTOHTML + ' -enc UTF-8 -noframes -p -nomerge "%s" "%s"'%(pathtopdf, os.path.basename(index))
+    cmd = (PDFTOHTML, '-enc', 'UTF-8',  '-noframes',  '-p',  '-nomerge',  pathtopdf, os.path.basename(index))
     cwd = os.getcwd()
     
     try:
         os.chdir(tdir)
-        p = subprocess.Popen(cmd, shell=True, stderr=subprocess.PIPE, 
-                             stdout=subprocess.PIPE)
+        p = popen(cmd, stderr=subprocess.PIPE, stdout=subprocess.PIPE)
         logger.info(p.stdout.read())
         ret = p.wait()
         if ret != 0:
diff --git a/windows_installer.py b/windows_installer.py
index 110899e8af..6e57003a73 100644
--- a/windows_installer.py
+++ b/windows_installer.py
@@ -27,9 +27,8 @@ ShowUnInstDetails show
 
 ;------------------------------------------------------------------------------------------------------
 ;Include Modern UI
-  !include "AddToPath.nsh"
-  !include "XPUI.nsh"
-  !define XPUI_SKIN "Windows XP"
+  !include "MUI2.nsh"
+  !include "WinMessages.nsh"
   
 ;------------------------------------------------------------------------------------------------------
 ;Variables
@@ -37,7 +36,7 @@ Var STARTMENU_FOLDER
 Var MUI_TEMP
 
 !define PRODUCT_NAME "%(name)s"
-!define XPUI_BRANDINGTEXT "${PRODUCT_NAME} created by Kovid Goyal"
+BrandingText "${PRODUCT_NAME} created by Kovid Goyal"
 !define PRODUCT_VERSION "%(version)s"
 !define WEBSITE "https://calibre.kovidgoyal.net"
 !define DEVCON  "C:\devcon\i386\devcon.exe"
@@ -48,6 +47,168 @@ Var MUI_TEMP
 !define PDFTOHTML    "C:\pdftohtml\pdftohtml.exe"
 !define IMAGEMAGICK  "C:\ImageMagick"
 
+
+; ---------------PATH manipulation -----------------------------------------------------------------
+; Registry key for changing the environment variables for all users on both XP and Vista
+!define WriteEnvStr_RegKey 'HKLM "SYSTEM\CurrentControlSet\Control\Session Manager\Environment"'
+
+Function Trim ; Added by Pelaca
+        Exch $R1
+        Push $R2
+Loop:
+        StrCpy $R2 "$R1" 1 -1
+        StrCmp "$R2" " " RTrim
+        StrCmp "$R2" "$\n" RTrim
+        StrCmp "$R2" "$\r" RTrim
+        StrCmp "$R2" ";" RTrim
+        GoTo Done
+RTrim:  
+        StrCpy $R1 "$R1" -1
+        Goto Loop
+Done:
+        Pop $R2
+        Exch $R1
+FunctionEnd
+
+; input, top of stack = string to search for
+;        top of stack-1 = string to search in
+; output, top of stack (replaces with the portion of the string remaining)
+; modifies no other variables.
+;
+; Usage:
+;   Push "this is a long ass string"
+;   Push "ass"
+;   Call StrStr
+;   Pop $R0
+;  ($R0 at this point is "ass string")
+ 
+!macro StrStr un
+Function ${un}StrStr
+Exch $R1 ; st=haystack,old$R1, $R1=needle
+  Exch    ; st=old$R1,haystack
+  Exch $R2 ; st=old$R1,old$R2, $R2=haystack
+  Push $R3
+  Push $R4
+  Push $R5
+  StrLen $R3 $R1
+  StrCpy $R4 0
+  ; $R1=needle
+  ; $R2=haystack
+  ; $R3=len(needle)
+  ; $R4=cnt
+  ; $R5=tmp
+  loop:
+    StrCpy $R5 $R2 $R3 $R4
+    StrCmp $R5 $R1 done
+    StrCmp $R5 "" done
+    IntOp $R4 $R4 + 1
+    Goto loop
+done:
+  StrCpy $R1 $R2 "" $R4
+  Pop $R5
+  Pop $R4
+  Pop $R3
+  Pop $R2
+  Exch $R1
+FunctionEnd
+!macroend
+!insertmacro StrStr ""
+!insertmacro StrStr "un."
+
+Function AddToPath
+  Exch $0
+  Push $1
+  Push $2
+  Push $3
+  ; don't add if the path doesn't exist
+  IfFileExists "$0\*.*" "" AddToPath_done
+  
+  ReadEnvStr $1 PATH
+  Push "$1;"
+  Push "$0;"
+  Call StrStr
+  Pop $2
+  StrCmp $2 "" "" AddToPath_done
+  Push "$1;"
+  Push "$0\;"
+  Call StrStr
+  Pop $2
+  StrCmp $2 "" "" AddToPath_done
+  GetFullPathName /SHORT $3 $0
+  Push "$1;"
+  Push "$3;"
+  Call StrStr
+  Pop $2
+  StrCmp $2 "" "" AddToPath_done
+  Push "$1;"
+  Push "$3\;"
+  Call StrStr
+  Pop $2
+  StrCmp $2 "" "" AddToPath_done
+  
+  ReadRegStr $1 ${WriteEnvStr_RegKey} "PATH"
+    StrCmp $1 "" AddToPath_NTdoIt
+      Push $1
+      Call Trim
+      Pop $1
+      StrCpy $0 "$1;$0"
+    AddToPath_NTdoIt:
+      WriteRegExpandStr ${WriteEnvStr_RegKey} "PATH" $0
+      SendMessage ${HWND_BROADCAST} ${WM_WININICHANGE} 0 "STR:Environment" /TIMEOUT=5000
+      
+  AddToPath_done:
+    Pop $3
+    Pop $2
+    Pop $1
+    Pop $0
+FunctionEnd
+
+Function un.RemoveFromPath
+  Exch $0
+  Push $1
+  Push $2
+  Push $3
+  Push $4
+  Push $5
+  Push $6
+ 
+  IntFmt $6 "%%c" 26 # DOS EOF
+  
+  ReadRegStr $1 ${WriteEnvStr_RegKey} "PATH"
+    StrCpy $5 $1 1 -1 # copy last char
+    StrCmp $5 ";" +2 # if last char != ;
+      StrCpy $1 "$1;" # append ;
+    Push $1
+    Push "$0;"
+    Call un.StrStr ; Find `$0;` in $1
+    Pop $2 ; pos of our dir
+    StrCmp $2 "" unRemoveFromPath_done
+      ; else, it is in path
+      # $0 - path to add
+      # $1 - path var
+      StrLen $3 "$0;"
+      StrLen $4 $2
+      StrCpy $5 $1 -$4 # $5 is now the part before the path to remove
+      StrCpy $6 $2 "" $3 # $6 is now the part after the path to remove
+      StrCpy $3 $5$6
+ 
+      StrCpy $5 $3 1 -1 # copy last char
+      StrCmp $5 ";" 0 +2 # if last char == ;
+        StrCpy $3 $3 -1 # remove last char
+ 
+      WriteRegExpandStr ${WriteEnvStr_RegKey} "PATH" $3
+      SendMessage ${HWND_BROADCAST} ${WM_WININICHANGE} 0 "STR:Environment" /TIMEOUT=5000
+ 
+  unRemoveFromPath_done:
+    Pop $6
+    Pop $5
+    Pop $4
+    Pop $3
+    Pop $2
+    Pop $1
+    Pop $0
+FunctionEnd
+
 ;------------------------------------------------------------------------------------------------------
 ;General
 
@@ -64,9 +225,6 @@ Var MUI_TEMP
   ;Vista redirects $SMPROGRAMS to all users without this
   RequestExecutionLevel admin
   
-  ; Manipulate the PATH variable for all users, not just the installing user.
-  !define ALL_USERS
-  
 ;------------------------------------------------------------------------------------------------------
 ;Interface Settings
 
@@ -383,6 +541,10 @@ class BuildEXE(build_exe):
         cwd = os.getcwd()
         try:
             os.chdir(os.path.join('src', 'calibre', 'gui2', 'pictureflow'))
+            if os.path.exists('release'):
+                shutil.rmtree('release')
+            if os.path.exists('debug'):
+                shutil.rmtree('debug')
             subprocess.check_call(['qmake', 'pictureflow-lib.pro'])
             subprocess.check_call(['mingw32-make', '-f', 'Makefile.Release'])
             os.chdir('PyQt')