Remove previous InnoSetup install

packages/putty.xml

@@ -5,18 +5,22 @@
              revision="3"
              priority="10"
              reboot="false">
- 
+
         <variable name="PKG_VERSION" value="0.68" />
         <variable architecture="x86" name="INSTALL_PATH" value="%PROGRAMFILES%\PuTTY" />
         <variable architecture="x64" name="INSTALL_PATH" value="%PROGRAMFILES(x86)%\PuTTY" />
- 
+
         <check type="uninstall" condition="versiongreaterorequal" path="PuTTY release %PKG_VERSION%" value="%PKG_VERSION%"/>
  
+        <install cmd='%COMSPEC% IF EXIST "%INSTALL_PATH%\unins000.exe" "%INSTALL_PATH%\unins000.exe" /silent /norestart'>
+            <exit code='0' />
+            <exit code='1' />
+        </install>
         <install cmd='msiexec /qn /norestart /i "%SOFTWARE%\putty\putty-%PKG_VERSION%-installer.msi"' />
- 
+
         <upgrade include='install' />
         <downgrade include='install' />
- 
+
         <remove cmd='msiexec /qn /norestart /x "%SOFTWARE%\putty\putty-%PKG_VERSION%-installer.msi"' />
       </package>
 </packages>