Setting the From header causes issues with new exchange server connection on windows platforms

I was getting an error:

Warning: mail() [function.mail]: SMTP server response: 501 5.1.7 Invalid address

when trying to forward pages.

I found the solution on an osTicket forum:

http://www.osticket.com/forums/showthread.php?t=702

By following the advice in the above forum thread I changed the code in the forward.module to the following:

line 770 from:
$params['from'] = trim($form_state['values']['yname'] .' <'. variable_get('forward_sender_address', variable_get('site_mail','')) .'>');

To:
$params['from'] = trim(variable_get('forward_sender_address', variable_get('site_mail','')));

This resolved the error and allows me to continue to forward via email.