Outlook express Compacting messages disable

Dear All,

I am using outlook express 6 for my pop mails.After couple of days when i
close the outlook express , it starts COMPACTING MESSAGES automatically.Once
the compacting finished, most of thetime i loose some of the recent mails in
INbox or sent items or in sub folders.

In earlier version outlook express, i used to get messege : do you want to
compact message "" if i say NO everything will be fine.

But in Outlook express 6 which i am using compacting happens
automatically,atleast once in week.

I am really frustrated.

ANybody can please help me to disable the COMPACT OF MASSAGES ?????

pLEASE HELP ME

THANK YOU
RAJESH