Mail not Sent; saved in Drafts and not Sent

I have a user that is having difficulty sending mail from her Notes client; when she hits the ‘send’ button, mail is not sent. Instead, it is being saved to the Drafts folder, and does not appear in Sent as expected.

The problem is intermittent and has occurred about 50% of the time today.

Any insight guys?..

Subject: Try to reinstall client and replace template

Could you please try to reinstall client and replace template again, and see if the intermittent problem still occur/