It isn't how many, it's the size if the folders.

General precautions for Outlook Express:

Do not archive mail in default OE folders. They will eventually become
corrupt. Create your own user defined folders for storing mail and move your
mail to them. Empty Deleted Items folder regularly. Keep user created
folders under 100MB, and Default folders as empty as is feasible.

After you are done, follow up by compacting your folders manually while
working *offline* and do it often.

Click on Outlook Express at the top of the folder tree so no folders are
open. Then: File | Work Offline (or double click Working Online in the
Status Bar). File | Folder | Compact all folders. Don't touch anything until
the compacting is completed.

Turn off e-mail scanning in your anti-virus program. It is a redundant layer
of protection that eats up CPUs and causes a multitude of problems such as
time-outs and account setting changes. Your up-to-date A/V program will
continue to protect you sufficiently. For more, see:
http://www.oehelp.com/OETips.aspx#3

In Tools | Options | Maintenance: Uncheck Compact messages in background and
leave it unchecked. {N/A if running XP/SP2}.

And backup often.

Backup & Resto
http://www.insideoe.com/backup/

This is a great two click program:

Outlook Express Quick Backup (OEQB)
http://www.oehelp.com/OEBackup/Default.aspx
--
Bruce Hagen
MS-MVP Outlook Express
Imperial Beach, CA


"MAT" wrote in message
...
In my outlookexpress folder I had approx. 26.000 mails and 930 MB of
mails. When I worked with other programs I sometimes got an error and
windows were freezing. After having deleted some attached files and
compressing all files/folder I now have approx. 600 MB of mails and no
problems with freezing windows.
I have 1 GB RAM and was just wondering what is the maximum amount of
e-mails using OE? Is it depending on how much RAM you have?