Hello,
I'm trying to store their products in my store but it is a problem with the calculation of VAT to 21%.
Example if I put a product that costs 15 € to 21% the tax should be € 2.60.
virtuemart calculates the VAT to 21% of this amount € 3.15 (15.00 €) instead of 2.60 €
I hope I explained myself, and I apologize for my bad English :-[
Looks like you have entered the final (retail) price as the cost price, which in your example probably is similar to the base price. 15€ x 1.21 = 18.15€.
If you want a final retail price of 15€, you would have to enter 12.3967 (15 : 1.21).
However I wouldn't recommend to use VM2 this way. It would be better to use a commercial business principle and configure a cost based pricing, i.e. enter your cost price (what you have to pay to your supplier), if necessary convert it into your local currency using the current rate of exchange (see VM2 currencies configuration), then add your profit margin with a 'calculation rule' and last but not least add your local sales tax.
then produced for profitable deals I put hand to the calculator and do the spin-off of VAT manually? :o
But in the version that was automatically 1x vm :'(
You can try version 2.0.3.E from here, where you can enter your final price and reverse the calculation. It currently still has a small bug, but might be ok for your case.
http://forum.virtuemart.net/index.php?topic=99590.0 (http://forum.virtuemart.net/index.php?topic=99590.0)