Miguel Balparda

[Here](https://github.com/nexcess/magento-turpentine/wiki/Usage) is the Wiki section explaining how to use the Activate Varnish Bypass feature. Also, the issue you are experiencing is not related to Varnish but to an incompatible theme...

This seems to be just a coincidence. You removed the unsetData from this block when you changed the XML, my guess is that you will have the same effect just...

What have you tried so far to debug this? It seems this might be related to the incorrect use of public and private, check the access node [here](https://github.com/nexcess/magento-turpentine/wiki/ESI_Cache_Policy#what-are-the-parameters-for-defining-a-cache-policy).

There are a couple of SID related configs in Turpentine's admin and SID is also included by default in some admin fields too, have you checked that?

Have you tried using JS in the frontend instead of PHP for the cookie changes?

PHP in the best scenario will never do anything since all you see will be cached and served by Varnish. What you might be able to do is to use...

What have you tried so far? Have you checked the [wiki](https://github.com/nexcess/magento-turpentine/wiki)?

You should check your PHP logs to see the exact cause of the issue and once you have that we might be able to help you.

That might be because of a miss configuration in your webserver or an @ suppressing the error. I suggest you to try to find the actual cause of the error,...

Did you find the cause or anything on the logs about the 500 error?