EXM issue with unsubscribe

Question

We are using sitecore 8.2 update 1 with EXM. Mailing campaigns isn't a problem but then when the user clicks on the unsubscribe link they don't see any success message. It's just empty page. Sometimes we see '404' page and sometimes its empty.

Server configuration is 1 CM + 1 CD server. On CD, AnalyticsClusetername is set to one of the site's host name and AnalyticsHostname is empty.

Also, the FinalConfirmation page is also set on the exm manager root,

In templates (both EXM OOB and custom templates) the link to unsubscribe is set as /sitecore/Unsubscribe.aspx But still the unsubscription doesn't work. No message and the contact is not added to global opt-out list.

Logs show the below message. Apart from it, there are no significant errors:

The query string received for this event was not marked as valid. The event will not be handled.

Answer 1

Links in EXM Messages are encrypted so that specific information isn't exposed during transport of message. When you click on a link from an Email, the link itself will look like

http://sxp82u5/sitecore%20modules/Web/EXM/RedirectUrlPage.aspx?ec_eq=a1RjRKjLKV5gDrslLHQx7gHmkUgwzYSNE9cf1pv9yxoJh%2fovjXuOjJPrx954I136BydyCImct43XRXHURKm4ngWOd1s2%2b0RJad4ZFvPK1Q65sSyIrVCLu24omoZqaDZ%2bB9bzIrLKtyQvwVgkhdNfizLGabmrPz7tNtzPqnVs70AgxleZM3PE6oEV4z9PPFP%2fh7eB1%2bGpj97ubU%2b4P3e7%2bkMYjtHOWIysMBuKzvXskqfU0wt5AZg1bWSlnmZ%2f1NPHwQKAKQCft7hnTbTG8abqg3yDM3co1JhHUOr66uNWPmbFzzAZEIDq60Ct4eHdPWpOGGt3CZgIAHZUuNB6PD%2bLqDEMzn0giwOG7ZKblDqzEBqTpH50Cdnuuic7wFUHSCUZ

The RedirectUrlPage.aspx executes the <redirectUrl> EXM pipeline. The first processor in this pipeline does the decryption. However, both the CM and the CD server need the same encryption keys set in the ConnectionString.config.

If these keys are wrong or not set on the CD server, the CD server will not know how to decrypt the URL, thus causing the error you're seeing.

Hope this helps!

Answer 2

This issue is solved. Actually, the crypto keys of exm on CD and CM servers were different. They should be same. After making the keys same on CD n CM, it started working.