Outlook Express problem - are any others afflicted?

[#1]

This is really a question for the Microsoft help and support forums, but I just thought I'd ask if anyone else is suffering the same problem as I've had since about a month ago with Outlook Express.
Symptoms are:  when I'm in OE with all apparently normal, and try to open an email (new or old) in my Inbox, up pops a window saying
"Message could not be displayed.
Outlook Express encountered an unexpected problem while displaying this message.
Check your computer for low memory or low disk space and try again."
At the same time, it is impossible to delete any messages;  and when I open another OE mail folder - like Sent items - there's no list of messages (nor the usual 'there are no messages in this folder').
Closing down OE and then reopening it seems to return things to normal, but only temporarily.  And the problem seems to be occurring increasingly often.
The Microsoft Knowledge Base suggests that McAfee AV programs may cause this:  but I don't have McAfee...
Incidentally I  use a Dell Inspiron 8600 laptop running XP Pro SP2, and with IE6 browser and and OE6 for email, fully updated.  There's 512MB RAM, and a 60GB hard disc of which 79% is still 'free'. I have very few additional programs, don't subscribe to newsgroups, and run ZoneAlarm firewall and AVG antivirus.  Some posts on other forums suggest that one possible cause might be if you leave, or store, large volumes of mail in the OE folders and don't compact them.  I have some  mail sitting in OE folders, but I have checked the .dbx files and they are pretty small.
Bottom line is that - so far - all the info I have seen indicates that neither Microsoft nor anyone else has identifed the cause of the problem, and there are suspicions that because it seems to be a problem for those running OE under Windows XP, Microsoft isn't bothered about finding a fix.
If this sounds familiar, and if anyone can point me towards a solution, I'd appreciate it (oh yes, I know one option is to go over to Thunderbird, and I'm seriously considering doing so.  But that's a bit of a cop-out!)
br1anstorm

[#2]

Try a repair job? (then get Thunderbird  )
http://www.microsoft.com/windows/ie/community/columns/oerepair.mspx

[#3]

This link might also be useful.
http://www.microsoft.com/windows/IE/community/columns/filecorruption.mspx
bobp

[#4]

Much-delayed thanks to those who replied to my original post on this topic.  The links suggested are useful for good housekeeping of OE, but it seems there is a specific issue, which may be of interest/concern to others.
This Outlook Express problem has been the subject of huge discussion over the last couple of months in the Microsoft Community groups, and also on the McAfee forums and the forums at AumHa.  Evidently quite a lot of people have been afflicted by the Outlook Express misbehaviour.
There's no clear fix or solution yet.  But the finger of blame is pointing pretty conclusively at McAfee Site Advisor - whether installed as a standalone program or as part of a McAfee Security Suite.  Strangely, SA is supposed to operate in browsers (IE and Firefox), vetting website 'safety'.  But since SA was last updated in early September, it has been interfering with OE and causing the "Message could not be displayed/low memory" popup.
For anyone who is interested, much of the discussion about how to identify and resolve the problem is at the MS discussion in this forum:
MS Forum
If anyone else is running OE and has McAfee Site Advisor too, can I suggest they check this out - and if you have the problem, report it, in this or other forums.
br1anstorm

[Moderator's note by billbo: Overly long url link chagned]

[#5]

One solution I've done in the past is to create a new identity and import your original messages / folders into the new identity.
Can't remember the exact key presses, but if you get stuck I can try and remind myself and let you know.
Jeff

[#6]

Jeff - I've never tried it, and I gather that creating a new identity and importing all folders etc is not the easiest of tasks.  But it is clear from the MS forums that some who have the Outlook Express problem have indeed tried exactly that, only to find that the problem persists, or reappears, in their OE under the new identity.  Similarly, cleaning up and deleting old emails - while good housekeeping practice - doesn't prevent or cure the problem.
All the evidence seems to suggest that the OE problem kicks in when the "handles" count in Task Manager hits a ceiling. Reading emails in HTML format, and especially with McAfee Site Advisor running, evidently pushes up the "handles" count rapidly, to the point where OE runs out of capacity and says it can't display (or delete) messages.  Uninstalling Site Advisor, or reading emails in plain text, keeps the "handle count" low and avoids the problem.
The unanswered question is - what exactly are "handles", and what makes the number increase as you use OE?  I'm hoping that someone on the MS forums will come up with an explanation - as that should open the way to resolving the problem.
None of this, of course, is Plusnet-related!  I only posted here originally in case fellow members of the PlusNet community had also suffered the OE problem and/or discovered the solution.
br1anstorm

[#7]

There is certainly no harm to be had by trying the creating a new identity route, I have just reminded myself and all it takes are a few key presses and voila its done.
Jeff

[#8]

Quote from: br1anstorm

All the evidence seems to suggest that the OE problem kicks in when the "handles" count in Task Manager hits a ceiling.… The unanswered question is - what exactly are "handles", and what makes the number increase as you use OE?  I'm hoping that someone on the MS forums will come up with an explanation - as that should open the way to resolving the problem.

This is not the place to enter a long discussion of "handles" but there is a short explanation here.  Too many handles (crudely open files or memory references which need buffers looking after) are an application management nightmare in terms of keeping communications between two independently written applications synchronised.  Needless to say, if this breaks down (and the chances of that are high) hang-ups/ timeouts/ memory shortages are likely.  Keeping the handle count down reduces the risk of problems.
Please note, this isn't meant to be a precise description of what handles are, it's a very rough guide to the problems and avoiding them.  Plain text can require fewer handles than HTML because complex formatting isn't needed.

[#9]

Quote from: spraxyt

This is not the place to enter a long discussion of "handles" but ....   Too many handles (crudely open files or memory references which need buffers looking after) are an application management nightmare ...  Keeping the handle count down reduces the risk of problems. ...  Plain text can require fewer handles than HTML because complex formatting isn't needed.

Quite right, spraxyt, and I did flag up that I was posting about this mainly in case others had encountered the same problem and were as puzzled as me about the cause.  Thanks for such a clear explanation.
The mystery remains:  what has suddenly caused my (and many others') Outlook Express to generate such a huge increase in the "handles" count and to suffer memory shortage as a result.  This started in September, and the circumstantial evidence indicates that it coincided with the latest update to McAfee Site Advisor.  Which still seems odd, because SA is a browser app, and isn't obviously supposed to operate in OE!
Anyhow, no need to prolong this thread - though it would still be interesting to know if anyone else has this OE problem;  and if so, do they also have Site Advisor, or might other apps also cause this problem?