Event 6875 Error Help

Hello,

We are running Sharepoint Foundation 2010 on a server and the event viewer keeps reporting the same errors.

Error loading and running event receiver TaskAlert.Assigner in 
TaskAlert, Version=1.0.0.0, Culture=neutral,PublicKeyToken=8c9fc716f38d08b2
. Additional information is below.

: Object reference not set to an instance of an object.

Log Name: Applicatoin
Source: Sharepoint Foundation
Event ID: 6875
Level: Error

Does anyone have any idea what could be causing this?