strange price problems; urgent

[lazyeye]

Hello,

I have a product at 19.99 euros excluding the 19.6% tva. In the database, the product's price is 19.99, on the site, the price is displayed including taxes (i.e. 23.91) but when I click on the add to cart button, the price listed on the confirmation page becomes 42.82!! If I confirm and go to the cart page, the price becomes 39.98. With shipping and tva (yes, again) my bill totals 55 euros.
I've checked everything but cannot find what is causing this error! I would appreciate urgent help from anyone who knows what I'm talking about.

Thanks

[RuralWeb]

URL???

[lazyeye]

hold your horses...

problem is solved now.

[RuralWeb]

Dont post as urgent next time then!

[lazyeye]

well, excuse me. I won't do it again. But at posting time the issue was urgent since the site was live. I did not have any idea of what was going on until I discovered that this was due to misconfiguration in product pricing method.
Again, I'm sorry.

[pinbrook]

could you tell us the solution for future reference?

[lazyeye]

Most of the products have components (size and/or color) and each permutation is set to associated product price. However, the pricing model (in the container product) was set to sum of product and component prices instead of sum of component prices.