emails stay on Outbox

[mm]

I'm runnning an XP SP2, with Outlook 2003. I do have NAV corporate 10 and use
a plug -in 'Exchange-It' with outlook.
Most of the time, i don't have problems when sending emails, but sometimes,
they just stay on the Outbox.
I have tried turning off NAV, this exchange-it thing, and it still happens
some times.
Some times i can send them if i move the unsent emails to a different
folder, close outlook, open it again, and move again the emails to outbox,
some times this works, some times i just close outlook and open it again, and
the emails are sent immediately
I have read somewhere to enable the logging on outlook, and i did it, and
this is what it says when the messages are not sent:

2006.11.02 14:15:34 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:15:34 192.168.1.131: Synch operation completed
2006.11.02 14:15:54 192.168.1.131: Synch operation started (flags = 00000001)
2006.11.02 14:15:54 192.168.1.131: UploadItems: 1 messages to send
2006.11.02 14:15:54 SMTP (192.168.1.131): Begin execution
2006.11.02 14:16:01 192.168.1.131: Synch operation queued
2006.11.02 14:16:09 SMTP (192.168.1.131): End execution
2006.11.02 14:16:09 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:16:09 192.168.1.131: Synch operation completed
2006.11.02 14:16:09 192.168.1.131: Synch operation dequeued (flags = 00000001)
2006.11.02 14:16:09 192.168.1.131: Synch operation started (flags = 00000001)
2006.11.02 14:16:09 192.168.1.131: UploadItems: 2 messages to send
2006.11.02 14:16:09 SMTP (192.168.1.131): Begin execution
2006.11.02 14:16:24 SMTP (192.168.1.131): End execution
2006.11.02 14:16:24 SMTP (192.168.1.131): Begin execution
2006.11.02 14:16:24 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:16:39 SMTP (192.168.1.131): End execution
2006.11.02 14:16:39 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:16:39 192.168.1.131: Synch operation completed
2006.11.02 14:16:59 192.168.1.131: Synch operation started (flags = 00000001)
2006.11.02 14:16:59 192.168.1.131: UploadItems: 2 messages to send
2006.11.02 14:16:59 SMTP (192.168.1.131): Begin execution
2006.11.02 14:17:14 SMTP (192.168.1.131): End execution
2006.11.02 14:17:14 SMTP (192.168.1.131): Begin execution
2006.11.02 14:17:14 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:17:29 SMTP (192.168.1.131): End execution
2006.11.02 14:17:29 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:17:29 192.168.1.131: Synch operation completed
2006.11.02 14:18:10 192.168.1.131: Synch operation started (flags = 00000001)
2006.11.02 14:18:10 192.168.1.131: UploadItems: 2 messages to send
2006.11.02 14:18:10 SMTP (192.168.1.131): Begin execution
2006.11.02 14:18:25 SMTP (192.168.1.131): End execution
2006.11.02 14:18:25 SMTP (192.168.1.131): Begin execution
2006.11.02 14:18:25 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:18:40 SMTP (192.168.1.131): End execution
2006.11.02 14:18:40 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:18:40 192.168.1.131: Synch operation completed
2006.11.02 14:19:20 192.168.1.131: Synch operation started (flags = 00000001)
2006.11.02 14:19:20 192.168.1.131: UploadItems: 2 messages to send
2006.11.02 14:19:20 SMTP (192.168.1.131): Begin execution
2006.11.02 14:19:35 SMTP (192.168.1.131): End execution
2006.11.02 14:19:35 SMTP (192.168.1.131): Begin execution
2006.11.02 14:19:35 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:19:50 SMTP (192.168.1.131): End execution
2006.11.02 14:19:50 192.168.1.131: ReportStatus: RSF_COMPLETED, hr =
0x8004210b
2006.11.02 14:19:50 192.168.1.131: Synch operation completed


Can some body help me and translate this to a human language pleeease??
thanks in advance for your help