Calculations error

The coupon calculations are not right. See this link for the way I have the coupon set up
http://www.th-webdevelopment.com/coupon-setup.jpg

And here is a link to show how the coupon is 10.00, but takes off 20.00 in the total.
http://www.th-webdevelopment.com/Cart_1270557543269.png

We really love your component and want to use it.

The coupon is set up generically, not related to a user or product.

Hmm, I have seen this error before. I believe this is a vm bug. To test, uninstall awocoupon and create a coupon with a different code in vm with total of 10. You should receive the same error. I only receive this error when "Subtract payment discount before tax/shipping?" is checked in admin->components->virtuemart->configuration->global tab. So it must be something to do with the way its calculating tax. Might be worth it to browse vm forum to see if there is a fix for it. One thing to note though, if you go through the whole order process and get to the confirmation page, the order corrects itself on that page. So all though it looks wrong, by the time the customer actually orders, its correct.

I have the same problem, is there a solution?
Thanks

Assuming you are using Virtuemart 1.1.4 and have discounts before tax, then yes this is a problem, within Virtuemart. I wrote a blog about it to help you get out of the mud.

https://awodev.com/blog/virtuemart-coupon-error-discount-before-tax

Also Virtuemart has come out with a new version, 1.1.5, where they claim to have fixed this. I have not tested it. So that is another option.