Why did the SharePoint event receiver stop firing?

Question

I have a SharePoint 2010 solution. I have a List Definition and an event receiver associated with the definition. I have a list instance associated with the definition. The event receiver has a single method, ItemDeleting, that was working for several days up until some point yesterday.

I am working off my dev box, 2008R2, and am deploying directly from VS2010. When I set a breakpoint and delete an item on the list I never hit the break point. I built the package and deployed the solution to a demo box and the event receiver does fire there just not on my dev box any longer. I have dropped the content database and restored and tried a few other things but the event still will not fire.

Where should I look to resolve this issue?

Answer 1

I had a similiar issue happen where a click event never made it to the handler just as if the event had been swallowed. In my case, I finally found that an exception had been thrown which short-circuited the event.

Check for a exception being thrown somewhere.

Answer 2

Check if the DLL that contains the Event Receiver is located in the GAC.
It could be a deployment problem.
Have a look at the "manifest.xml".