The subject behavior occurs because the the Windows 2000 Fax Transport service is NOT replaced with the Windows XP Fax Transport service because both services have the same name.
To resolve this behavior:
Outlook 2003
01. Open Outlook 2003.02. Select E-mail Accounts on the Tools menu.
03. Press View or change existing e-mail accounts and press Next.
04. Select Fax Mail Transport and press Remove.
05. Press Yes to confirm.
06. Press Finish.
07. Press Exit on the File menu.
08. Restart Outlook.
09. On the Tools menu, select E-mail Accounts.
10. Press Add a new e-mail account and press Next.
11. On the Server Type page, press Additional Server Types.
12. Make sure that Fax Mail Transport is selected in the Additional Server Types list.
13. Press Next and Finish.
Outlook 2000
01. Open Outlook 2000.02. On the Tools menu, press Services.
03. On the Services tab, Select Fax Mail Transport and press Remove.
04. Press Yes to remove this service from the profile.
05. Press OK and OK.
06. Press Exit and Log Off from the File menu.
07. Restart Outlook.
08. On the Tools menu, press Services.
09. On the Services tab, Select Fax Mail Transport and press Add.
10. Press OK and OK.
