I have some code that sends out an email. If I run that code from inside salesforce it works fine. However, if I run that code as the public sites user I get the following SendEmailResult error.

SendEmail failed. First exception on row 0; first error: INVALID_CROSS_REFERENCE_KEY, invalid cross reference id: []

However, all the mailing objects ID's (who, what, template and orgwide) are exactly the same when I send it from inside salesforce and from the website so I don't understand how it could be giving an error in one case but not the other.

 Here's the code that sends the email:

Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage(); 

mail.setTemplateId(template);

mail.setwhatId(what);

mail.setTargetObjectId(who);

mail.setSaveAsActivity(true);

mail.setOrgWideEmailAddressId(orgwide);

Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail});

for(Messaging.SendEmailResult res : r){

if(res.isSuccess() == false)

System.debug(res.geterrors().get(0).getMessage());

}

 Am I misunderstanding the error or is there some other ID field that could be screwing up the email?