See www.oehelp.com/backup.aspx You need to backup the message store and the
relevant registry keys. Then, once reinstalled, just replace the location
of the message store and merge the registry keys. Then before starting
Winmail make sure the "Store Root" value in the registry correctly lists the
location of the message store and if so then start Winmail and it should
work fine, except you will have to put in your passwords again.