Problem is solved by complete reinstall of xp_smtp_sendmail

dbcc xpsmtp80(free)

exec sp_dropextendedproc 'xp_smtp_sendmail'

EXEC sp_addextendedproc 'xp_smtp_sendmail', 'xpsmtp80.dll'

grant execute on xp_smtp_sendmail to public

I've also receive this error message:

disconnecting from server failed.

Does anybody know where is problem?

Thanks