Send to Mail Recipient Won’t Sent

On a specific workstation (others work fine)
WIndows XP, SP2
Office 2003, SP2

1) Right click a file and select “sent to mail recipient” (or send to mail recipient from IE).

2) Outlook opens in a new message.

3) Send to address is entered (and valid).

4) Click “send.” Nothing happens.

Has anybody seen this before?

Thanks.