Thread: V9 ML, coupon causes tax on a $299 purchase to be -$6 (negative) not the correct $17.

We are using AspDotNetStorefront ML 9.0.1.3/9.0.1.2 and have a problem with taxes being calculated incorrectly (and a negative number at that) when a $100 coupon is used. Other coupons have been used for other products without adverse affects. Looking at the coupons table in the database, there is nothing out of the ordinary for this coupon. Details are as follows:

A product with a $399.00 cost had a simple $100 coupon applied to it, bringing the subtotal of a single product, tax class is Goods, down to $299. A sales tax of 6 percent, instead of being $299 x .06, or about $18, the tax came out at a negative $6.06. Any idea why the tax is coming up as a negative $6.06 rather than a positive $17.94? This is completely bizarre. I reviewed the coupon record and the taxes table in the database, nothing looks out of place. Using TaxCalcMode of "shipping."

Any info on this would be much appreciated!

Thank you,

- Kent

Well it looks like this thread is not exactly a hot one...in 2 years no replies, but here I am again, anyone out there have this same problem? Check this out:

I am using version ASPDNF ML 9.0.1.3/9.0.1.2. The storefront resides in PA and therefore for PA sales we apply sales tax. Something really weird is occurring where the charges should look like this:

Expected calculation:
-----------------------------
SubTotal: $99
Coupon: $60 discount amount (not percentage)
Net Subtotal: $39
Shipping: FREE SHIPPING
Tax: $2.34 (6%)
Total: $41.34

But instead, it looks like THIS…
------------------------------------------
SubTotal: $99
Net Subtotal: $39 (Subtracts $60 coupon amount correctly)
Shipping: FREE SHIPPING
Tax: -12.06 (??????????)
Total: $26.94

Have you traced the source code in debug mode to see exactly what is happening?