In my experience upgrading W98/OE/IE to 6, I had zero problems. The download is a little large, but worth it. If you feel better about saving messages and addresses, try this.
The messages are on the HD with an extension of .dbx. Do a search for them and save them to a CD. The address book is a .wab file, search for and save it also. There is a utility called Export in OE that will export and save the Address files, but not the messages. You can export the addresses or save them as stated above. I find exporting is a little faster.
Once You have upgraded, visit my site below, scroll down to the Software link, and download the OE Backup program. It will do all this for you including saving all settings and user accounts with just a few clicks.
Good luck,
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Presently running IE 5.5 and Outlook Express 5. This years Turbo Tax requires an upgrade to IE 6.0. I assume this means OE will also be upgraded. I have heard that with this OE upgrade you are likely to lose all saved messages and your saved address book. Step-by-step, how can I copy these items to a file and then re-install them in the new OE? I am running WIN 98 as OS. Thanks.

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