Yes, it likely has nothing to do with Google's end.
When tracking just stops working for no reason there are a few things that can cause it (all deal in some way with a change that was made on the website end or within the analytics themselves.)
1) Check to make sure that the tracking code is indeed appearing on your pages (including placing a test order and viewing the source on the checkout success page.)
2) Did you recently install any affiliate type program (in January) such as JAM affiliate? If so, the way they integrate that with zen cart overrides the code for Google Analytics. To get them both to work together you need to make a tweak to your site (moving the JAM affiliate code to a new location.)
Instructions to do that can be found here:
http://www.zencartoptimization.com/2...-the-workbook/
Scroll down the page to the "Comments" section. Around July 22, 2009 you'll find a post I made that specifically deals with how to correct the issue.
3) Check to make sure that the tracking ID used on your website is the same as the tracking ID shown in Google Analytics. I've seen this inadvertently changed at times. Do the same for the tracking ID for Adwords.
4) Make sure that you have "conversion tracking" turned on in the Zen CArt admin (under Google Analytics Configuration.)
It's likely that one of these issues is the culprit.
Give them a check and let me know if any solve your problem.
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