How to delete a gMail IMAP message from Outlook 2007

I apologize in advance on this question. I have tried to "google" it but it is very confusing.

 Outlook 2007

multiple POP and a gMail IMAP account in outlook profile.

 The gMail messages cannot be deleted. When the "x" on the message is applied, sometimes it gets a line through it. I tried "purge" but that did not work.

 Please give a reference as to how to delete gMail messages within Outlook 2007.

Thanks, in advance.

John Lenz