Check whether the option to "Compact messages in background" in Tools,
Options, Maintenance has been selected. It should be deselected as the use
of this option invariably leads to folder corruption and causes slow
performance.

Is there any evidence of folder corruption? Enter Windows Explorer. Using
Tools, Find, Files and
Folders search your C drive with "inbo*.db*" without quotes as the search
criteria and see if you can find more than one folder. The asterisks are
wild cards and should be included. Note the date / time stamp on the files
and the older folder will contain your missing messages.
The original inbox will appear as inbox. dbx. The next as inbox (01) dbx,
then inbox (02) dbx etc. The file extension can also appear as .dbt i.e. a
temporary folder.

http://www.tomsterdam.com/insideoe/problems/bugs.htm#mailgone

~~~~~~

Hope this helps.

Gerry
~~~~~~~~~~~~~~~~~~~~~~~~
FCA

Stourport, Worcs, England
Enquire, plan and execute.
~~~~~~~~~~~~~~~~~~~~~~~~
Please tell the newsgroup how any
suggested solution worked for you.
http://dts-l.org/goodpost.htm
~~~~~~~~~~~~~~~~~~~~~~~~

Look in your message store folder (Tools/Options/Maintenance and Store
Folder button) for files such as Inbox.dbx, Inbox(1).dbx, Inbox(2).dbx, etc.
Copy these to a new folder you create on your Desktop.  Then download a copy
of DBXtract ($5) from www.oehelp.com and run it within the same folder where
you saved the DBX files to extract the contents as eml files which can be
dragged/dropped into a local mail folder in Outlook Express (but, please not
back into the Inbox since the quantity of messages is the most probably
reason why the dbx file became corrupted).

See also the info at this link for some added ideas:
http://insideoe.tomsterdam.com/problems/bugs.htm#mailgone