Turn off PHP notices and warnings.

[jenkinhill]

Advisory notices and warnings from PHP are turned on by default in the php.ini provided in PHP5.3+  Edit php.ini to turn them off -  http://php.net/manual/en/function.error-reporting.php

These can be turned off by editing your server php.ini (which is the preferred way to solve this, but not permitted by some shared hosts), by using .htaccess or by simply changing the reporting level in Joomla. Go to Joomla 2.5/3.x's Global Configuration/Server/Server Settings/Error Reporting. For most users "Simple" is a good setting.

You can also turn these off in VM configuration, see message from Milbo below.

About php error messages:  http://www.ostraining.com/blog/joomla/warnings/?mc_cid=5f721f0d11

[Milbo]

VirtueMart has now an option to configurate it directly in VirtueMart if not set already by joomla.

Just to go to the VirtueMart config first tab. You can enable the messages for all or just admins, so even a life shop can partly debugged.