outgoing email problem - event id 681

Sometimes I work from home by dialing into our work network. I have Win XP Professional and Outlook XP at home and at work. I'm not sure which version of Exchange we're using. In the office I can send e-mail. The last few months at home I haven't been able to send e-mail while logged onto our work network. When I had Outlook 98 and Windows 98 I could send e-mail. For a brief time when I had Outlook XP and Windows 98 I could send e-mail. But then the problem started (after I was able to send e-mail with Outlook XP and Win 98). I don't remember changing anything on my computer to cause this problem.

I now have Win XP Pro and Outlook XP at home and still can't send e-mail. I can read, open and receive new e-mail. I just can't send e-mail. It stays italicized in my Outbox with the word Outbox (in the folder list) bolded.

Our Network IT guys have had some suggestions, but nothing's worked. I then asked if I could see anything in the Event Log (of which I'm not familiar). They told me I get Event ID 681 and 529 apparently when I try to send e-mail.

Earlier, I had set up my pc at home so it has my full name - I guess I did this when registering my software. I since changed it to just my last name - this matches my account name at work. However, the domain (that got created by default) at home is different than the domain we have to use at work. I changed it once at home weeks ago, but that didn't solve the problem.

Do you know if I should try to change my domain at home again (not sure if I remember how I changed it before), or is there a way for our network guy at work to give my home name and domain access to the Exchange server? Are the accounts and domain names case sensitive?

The description for event 681 refers to my account (my last name) and the workstation name (that I think Win XP created by default). The error code is 3221225572 (User logon with misspelled or bad user account).

Event 529 says I have an unknown user name or bad password. It has the same user name and domain as in event 681. It says the logon type is 3 and the logon process is NtLmSsp. Authentication Package is NTLM.

Most of this doesn't make sense to me and our Network guys are busy and either can't, or don't have time to, figure it out other than what they've already done. But if you could give me any info that I could pass along to our Network guys, or any info that would help me change something on my computer at home, I would appreciate it.

Thanks,

~Mark