We have an older SharePoint 2010 site. Is it possible to use a remote event receiver with a list?
The answer is no. I found useful information on a MSDN blog post, "A new concept of remote event receivers have been introduced in SharePoint 2013."
No you cannot create Remote Event Receiver in SharePoint 2010. In SharePoint 2010 you have a Event Receiver. But more than anything else I am concerned about why you want to use Remote Event Receiver in 2010 and in what context ?
Remote Event Receiver is a newly concept introduced SharePoint 2013. If you look at the solution of Remote Event Receiver you will see that it has 2 project one is WCF application and another is SharePoint APP. In short you can say that WCF service which is hosted some where else and will be listening to the event for which you have added. http://blogs.msdn.com/b/kaevans/archive/2014/02/26/attaching-remote-event-receivers-to-lists-in-the-host-web.aspx
Happy Coding, Thanks