WindowsXP 5.1 Removing communication and settings configurations

I have been unable to prevent Windows XP from removing my communication and setting configurations.

(ie) OE Pop mail server configurations. Windows claims my VPN's don't have drivers and I have to reinstall. I continually change mail to default to OE but the 'Set programs Access and defaults' application continually removes my settings. Upon booting, once Windows is loaded, the desktop message is 'Either there is no default mail client or the current mail client cannot fulfil the message request. Pease run Microsoft Outlook and set it as the default mail client.'

I don't want MO as default mail client and continually configure OE as default mail cleint. Windows removes all my configurations.

New PC ... One user, no passwords. On small local network. Basic Workstatkion.

Please advise how to resolve or refer to another source for information.

Thank you..