Help with xp_sendmail needed!

Hello,
I am using xp_sendmail SP to send emails to myself, not to a distribution list. I receive the error: Server: Msg 18031, Level 16, State 1, Line 0
xp_sendmail: Could not resolve recipient
The server is a MS Windows 2003 running SQL 2000 and Office XP SP3. The OS, SQL and Office are fully updated. I do not think that this problem is related to the bug described in Article ID:315666.
May I ask you for some help?
Thank you,
Ovidiu Tanjala
Hi Ovidiu,
Are you able to execute xp_stopmail and xp_startmail successfully? Also
please post your xp_sendmail statement, which resulted in this error.
Thanks
Yogish