title: How to upgrade virtuemart for joomla 1.5.26
body: <p>I have virtuemart version 1.1.7 was running on joomla 1.5.23.<br>
  Now I have upgraded to joomla 1.5.26, I need to upgrade virtuemart from 1.1.7 to 2.0.12 which is stable compatible one for joomla 1.5.x.<br>
  Any help on how to do this, I can't afford to install new version as all my user data will be lost in fresh installation of new version.</p>