"The question was, 'Have you rebooted?' not 'Do you believe that rebooting will help your situation?'"

To increase mail attachment sending limits look in one of two places.

1. Active Directory – domainName.nnn – Users – userName properties – Exchange General tab – Delivery Restrictions Button. Under the Sending or Receiving message size areas click the radio button for “Maximum KB” and set as desired. 1000 KB is approximately 1 MB (20,000KB = 20MB)
2. Exchange Server Manager: Under the “First Organization (Exchange)” open the Global Settings folder, then Message Delivery, and then Defaults to set the limit.