Invoice Total Issues

Our store has been up and running for about 9 months now, so far so good. However, this morning we received an order with a sub-total of $109.22, a shipping charge of $10.57, and it lists a total of $124.90 (even after a long weekend, i can see that this total is incorrect, and should be $119.79) This leaves a difference of $5.11, which is not the price of any items in our store.
We haven't noticed this on and past orders, and the few that we've received after this order appear correct. These is nothing "unusual" about this order, it uses a common shipping method, payment method, etc. no discounts to calculate, no sales tax to consider. i'd like to chalk this up to just a fluke, but i don't like the idea of having to review each order to ensure the total is correct.

i've searched the forums and found tons of threads about incorrect tax calcs, etc, but couldn't find anything on a random subtotal/total issue. i suppose this question is directed more toward the forum gurus, does anyone know of anything i should check to investigate this issue, or just wait to see if this repeats? the more i think about what possible causes there could be, the more i come back to thinking "why would it work for every other order, but not this one".
(screenshot attached)

thanks in advance..

I notice that it has amount paid $0 - What payment module are you using?

think i figured this one out - i just noticed that there was a tax definition for Maryland (the state we're located in) to charge 7% tax. we are a wholesaler, and only sell to retail stores - therefore, we do not charge sales tax. several of the items included in this order were entered as the default "taxable goods", instead of "none".. this was causing the gross price for each product to be calculated in the total, but not the sub-total.

We have a similar issue, everything has been running fine except for the latest order that we received.

The sub-totals are all correct and as follows;
Sub-Total: $363.54
Postage: $14.00
Group Discount: - $51.92
Quantity Discount: -$72.71
GST Tax: $21.90 (this amount is already calculated in totals)
Total: $240.49 - this amount should be $252.90

There is a diference of $12.42 which, not sure why.

There is nothing else unusual about this order, we have had previous orders with discounts etc and everything was fine.

Does anyone have any ideas what could be causing this?

(screenshot attached)

thanks.

www.jour.com.au

Anyone???

Please help :unsure:

Im having a similar issue. :wacko:
I've never seen it until now (testing Gift Certificate functionality)

Sub-Total: $510.00
Store Pickup (Walk In): $0.00
Sales tax: $35.70
Gift Certificates: -$500.00
Total $55.70

That total should be $45.70

Sales tax is correct - $35.70 = 7% of $510.

Anybody know what might be causing this?

Hi Spartan,

I have realised that the difference of $12.42 shown in my example
is the 10% tax amount of the Group & Quantity discounts. For some reason the system shows these amounts without the tax but then adds the tax to the total.

I'm not sure how to fix this as no one with a solution has responded to this thread.

Regards,
Phil.

www.jour.com.au

i have a similar problem after i have quantity discount installed :(

do you know how to fix it ?

Havn't found a solution for this issue yet...

This thread "ZC Getting Sums Wrong?"
http://www.zen-cart.com/forum/showthread.php?p=685376
also has examples of similar problems.

How many related threads are there on this issue?