I don't remember seeing this before, but on my checkout summary page, the line that displays the taxes isn't showing up. If I log in and place a test order, the tax is being calculated and added to the total, it's just not displaying on it's own line which it should be. Could someone point me in the direction I should look to correct this.

Thanks in advance.

We are having problem aswell, it will calculate taxes fine, but if we were to add another product or make any changes to the order for example by adding a processing fee, the tax will go to $0 and we won't be able to adjust the tax!

We've been having to add the tax in the processing fee which is going to confuse the customer when they receive their invoice and also it will make it very difficult for us when we do our paper work.

All of this happened to us after we did the site upgrade and I hope this problem will be resolved quickly.

I'm also having this same problem.

I have opened a support ticket.

Update.

Support emailed over an updated file.

Uploaded the file, ran a couple of test transactions and evrything appears to be working correctly. 

Just an update to the issue my store was having. Thanks to the excellent detective work by the Early Impact Technical Support Team, they were able to identify and fix the problem. It turns out that somehow the file "taxsettings.asp" located within the "includes" folder had the Canadian tax option set to on "1", when it should have been set to off "0". Here's the offending line of code:

private const ptaxCanada="1"

I just wanted to publicly thank everyone who helped in solving this issue.

Sorry for the late post, but just a few hours after sending in my support ticket, they sent the file and the problem is resolved...truly excellent support!