diff --git a/development/Win32/packaging/installer/download.nsh b/development/Win32/packaging/installer/download.nsh
index 7f4798833b..3382c50d36 100644
--- a/development/Win32/packaging/installer/download.nsh
+++ b/development/Win32/packaging/installer/download.nsh
@@ -298,7 +298,8 @@ go_on:
     StrCpy ${FolderPath} ""
     ExecShell open "${URL}"
   ${else}
-    ${StrTrim} ${FolderPath}
+    ${StrTrim} ${FolderPath} ${FolderPath}
+    ${StrRTrimChar} ${FolderPath} ${FolderPath} '\'
 
     ${if} ${FolderPath} == ""
       MessageBox MB_OK "${EnterFolder}"
@@ -307,8 +308,9 @@ go_on:
 
     ${if} ${FileExists} "${FolderPath}"
       ${StrRep} ${FolderPath} ${FolderPath} "${ExeName}" ""
+      ${StrRTrimChar} ${FolderPath} ${FolderPath} '\'
 
-      ${if} ${FileExists} "${FolderPath}${ExeName}"
+      ${if} ${FileExists} "${FolderPath}\${ExeName}"
       ${else}
         MessageBox MB_OK "${InvalidFolder}"
         Abort
diff --git a/development/Win32/packaging/installer/lyx_installer.nsi b/development/Win32/packaging/installer/lyx_installer.nsi
index 1e5038b930..2340150519 100644
--- a/development/Win32/packaging/installer/lyx_installer.nsi
+++ b/development/Win32/packaging/installer/lyx_installer.nsi
@@ -61,6 +61,9 @@ ${StrLoc}
 ${StrNSISToIO}
 ${StrRep}
 ${StrTrim}
+${StrLTrim}
+${StrRTrim}
+${StrRTrimChar}
 ${ReadDownloadValues}
 ${EnableBrowseControls}
 ${SearchRegistry}
@@ -369,7 +372,7 @@ Function DownloadMinSYS_LeaveFunction
       $MinSYSPath \
       "http://sourceforge.net/project/showfiles.php?group_id=2435&package_id=82721&release_id=158803" \
       "$(EnterMinSYSFolder)" \
-      "\sh.exe" \
+      "sh.exe" \
       "$(InvalidMinSYSFolder)"
 FunctionEnd
 
@@ -403,7 +406,7 @@ Function DownloadPython_LeaveFunction
       $PythonPath \
       "http://www.python.org/download/" \
       "$(EnterPythonFolder)" \
-      "\Python.exe" \
+      "Python.exe" \
       "$(InvalidPythonFolder)"
 FunctionEnd
 
@@ -438,7 +441,7 @@ Function DownloadMiKTeX_LeaveFunction
       $MiKTeXPath \
       "http://www.miktex.org/setup.html" \
       "$(EnterMiKTeXFolder)" \
-      "\latex.exe" \
+      "latex.exe" \
       "$(InvalidMiKTeXFolder)"
 FunctionEnd
 
@@ -473,7 +476,7 @@ Function DownloadPerl_LeaveFunction
       $PerlPath \
       "http://www.activestate.com/Products/ActivePerl/" \
       "$(EnterPerlFolder)" \
-      "\perl.exe" \
+      "perl.exe" \
       "$(InvalidPerlFolder)"
 FunctionEnd
 
@@ -524,7 +527,7 @@ Function DownloadGhostscript_LeaveFunction
       $GhostscriptPath \
       "http://www.cs.wisc.edu/~ghost/doc/AFPL/index.htm" \
       "$(EnterGhostscriptFolder)" \
-      "\gswin32c.exe" \
+      "gswin32c.exe" \
       "$(InvalidGhostscriptFolder)"
 FunctionEnd
 
@@ -559,7 +562,7 @@ Function DownloadImageMagick_LeaveFunction
       $ImageMagickPath \
       "http://www.imagemagick.org/script/binary-releases.php" \
       "$(EnterImageMagickFolder)" \
-      "\convert.exe" \
+      "convert.exe" \
       "$(InvalidImageMagickFolder)"
 FunctionEnd
 
diff --git a/development/Win32/packaging/installer/strtrim.nsh b/development/Win32/packaging/installer/strtrim.nsh
index a5857395b0..8a5af35211 100644
--- a/development/Win32/packaging/installer/strtrim.nsh
+++ b/development/Win32/packaging/installer/strtrim.nsh
@@ -3,10 +3,13 @@
 
 !include "lyxfunc.nsh"
 
+!insertmacro LYX_DEFFUNC `StrLTrim`
+!insertmacro LYX_DEFFUNC `StrRTrim`
 !insertmacro LYX_DEFFUNC `StrTrim`
+!insertmacro LYX_DEFFUNC `StrRTrimChar`
 
-!macro LYX_FUNCTION_StrTrim
-  !insertmacro LYX_FUNC `StrTrim`
+!macro LYX_FUNCTION_StrLTrim
+  !insertmacro LYX_FUNC `StrLTrim`
 
     ; After this point:
     ; $0 = String (input)
@@ -22,12 +25,35 @@ Loop:
     StrCmp "$1" "$\r" TrimLeft
     StrCmp "$1" "$\n" TrimLeft
     StrCmp "$1" "	" TrimLeft ; this is a tab.
-    GoTo Loop2
+    GoTo Done
 TrimLeft:
     StrCpy $0 "$0" "" 1
     Goto Loop
 
-Loop2:
+Done:
+    Pop $1
+    Exch $0
+  FunctionEnd
+!macroend
+
+!macro LYX_FUNCTION_StrLTrim_Call Output Input
+  Push `${Input}`
+  Call StrLTrim
+  Pop `${Output}`
+!macroend
+
+!macro LYX_FUNCTION_StrRTrim
+  !insertmacro LYX_FUNC `StrRTrim`
+
+    ; After this point:
+    ; $0 = String (input)
+    ; $1 = Temp (temp)
+
+    ; Get input from user
+    Exch $0
+    Push $1
+
+Loop:
     StrCpy $1 "$0" 1 -1
     StrCmp "$1" " " TrimRight
     StrCmp "$1" "$\r" TrimRight
@@ -36,7 +62,7 @@ Loop2:
     GoTo Done
 TrimRight:
     StrCpy $0 "$0" -1
-    Goto Loop2
+    Goto Loop
 
 Done:
     Pop $1
@@ -44,10 +70,58 @@ Done:
   FunctionEnd
 !macroend
 
-!macro LYX_FUNCTION_StrTrim_Call String
-  Push `${String}`
+!macro LYX_FUNCTION_StrRTrim_Call Output Input
+  Push `${Input}`
+  Call StrRTrim
+  Pop `${Output}`
+!macroend
+
+!macro LYX_FUNCTION_StrTrim
+  !insertmacro LYX_FUNC `StrTrim`
+    Call StrLTrim
+    Call StrRTrim
+  FunctionEnd
+!macroend
+
+!macro LYX_FUNCTION_StrTrim_Call Output Input
+  Push `${Input}`
   Call StrTrim
-  Pop `${String}`
+  Pop `${Output}`
+!macroend
+
+!macro LYX_FUNCTION_StrRTrimChar
+  !insertmacro LYX_FUNC `StrRTrimChar`
+
+    ; After this point:
+    ; $0 = Input
+    ; $1 = Char
+    ; $2 = Temp
+
+    ; Get input from user
+    Exch $0
+    Exch
+    Exch $1
+    Push $2
+
+    StrCpy $2 "$0" 1 -1
+
+    StrCmp "$2" "$1" TrimRight
+    GoTo Done
+TrimRight:
+    StrCpy $0 "$0" -1
+
+Done:
+    Pop $2
+    Pop $1
+    Exch $0
+  FunctionEnd
+!macroend
+
+!macro LYX_FUNCTION_StrRTrimChar_Call Output Input Char
+  Push `${Char}`
+  Push `${Input}`
+  Call StrRTrimChar
+  Pop `${Output}`
 !macroend
 
 !endif ; _STRTRIM_NSH_