Please Help. Add to cart not working!!!

[panosfar]

Hello everybody, i'm new here. Please, i need your help.
After upgrading from vm 2.0.20b to 2.0.22a the add to cart button is not working.
Actually, the product is added to cart normally but i get 500 - Layout "default" not found
error page.
I'm using Joomla 1.5.26.

Thanx.

[PRO]

no url to look at?

have you tried with a default joomla template?

[jenkinhill]

If possible please use Joomla 2.5.11  - Joomla 1.5 is no longer supported.  http://virtuemart.net/news/list-all-news/426-end-of-life-for-virtuemart-11-heidelpay-now-in-virtuemart-2012
"We decided to declare now the end of life for VirtueMart 1.1, and that the version 2 of VirtueMart is not any longer maintaining joomla 1.5 compatibility." 4 October 2012