Why the Campaign Tracking Parameters isn't working on Product Pages?

Question

I have a situation where I send out email campaigns which link back to products. The link code is in the format:

?utm_campaign=EnewsNov&utm_medium=email&utm_source=HouseList&utm_term=editorial-link&utm_content=header

When I add the tracking link to my domain i.e:

http://www.domain.com/?utm_campaign=EnewsNov&utm_medium=email&utm_source=HouseList&utm_term=editorial-link&utm_content=header

It works fine. It also works fine for category pages.

For Product pages however the link is broken and I get an error like:

This page isn’t working

www.mydomain.com redirected you too many times. Try clearing your cookies. ERR_TOO_MANY_REDIRECTS

If I however reduce the parameters to one i.e

http://www.domain.com/ANY_PRODUCT_URL/?utm_campaign=EnewsNov

It works fine. How can I fix this?

Answer 1

In our case the issue was caused by the Creare SEO extension.

Class::function:

Creare_CreareSeoCore_Model_Observer::forceProductCanonical()

Simply setting the creareseocore/defaultseo/forcecanonical config field to No solved this issue.

[System] -> [Configuration] -> [CREARE SEO] -> [General Settings] -> [Enable Canonical Product Redirecting]

This issue might also come from any other observer observing this event: catalog_controller_product_view

Disabling the module didn't prevent the observer from being executed. We had to comment out the entire function content to confirm it was the culprit.