On April 22nd, 2014 AOL.com implemented a change to their email system linked to a policy titled DMARC.

DMARC stands for Domain-based Message Authentication, Reporting & Conformance and it is an email authentication policy that aims to prevent spoofing and spamming linked to the "From" email address on messages.
 
The change prevents emails with a From address ending in @aol.com from being sent through systems outside of AOL. As a result, any messages sent from ACTIVE Works Camps or Class Manager using an AOL From address will be rejected. Updating your From email settings ensures your confirmation and broadcast emails continue to send successfully.
 
To update your confirmation email:
  1. Login to your organizations Camps and Class Manager database
  2. Click Setup under your season
  3. Click Confirmation Email
  4. Click Customize button
  5. Click Edit on From field
  6. Enter a non-AOL email address
  7. Click OK
  8. Click Save and Continue
 To update broadcast email From email addresses:
  1. Login to your organizations Camps and Class Manager database
  2. Click Email tab
  3. Click Templates
  4. Select a Template
  5. Click Edit on the From field
  6. Enter a non-AOL email address
  7. Click OK
  8. Click Save