Error - Send Email Extended

Dec 13, 2013 at 7:00 PM
Downloaded and installed per instructions. The Custom Actions are available in SharePoint Designer 2010.
Create a simple workflow to Send Email Extended - SPD shows no errors - save and publish - no problem.

Open SharePoint 2010 list and run the workflow and receive this error -

System.Net.Mail.SmtpException: Failure sending mail. ---> System.UnauthorizedAccessException: Access to the path 'D:\inetpub\mailroot\Pickup\edeceb8d-875c-4451-a891-d19bf2c54d25.eml' is denied.
at System.IO.__Error.WinIOError(Int32 errorCode, String m

OOTB send email workflows run with no problems.
Any suggestions would be appreciated.