How Order Number custmise
example :wpo/pro/0111
There will be a plugin for that.
I have now created such a plugin, which allows the shop owner to change the order number, order password and invoice number at will:
http://open-tools.net/virtuemart-2-extensions/40-vm2-ordernumber.html
The format is given as a text string, where [...] is understood as a variable and replaced by its value (e.g. [year] by the current year).
The running counter is indicated by #. The counter can be configured to be global (e.g. not reset each year/month/..) or a separate counter for each year/month/...
I hope you like the plugin and it does what you need.