Outlook 2010 - Public Folders difficult to access after adding multiple additional mailboxes into th

  • Thread starter Jim_1235
  • Start date Views 2,451


SBS 2008 / Exchange 2007

On a machine which has Office 2010 installed we are finding that after adding multiple additional mailboxes into the Outlook 2010 folder list accessing Public Folders gets slower and slower the more mailboxes you add in, to a point when you can no longer access any Public folders any more.

The mailboxes are added as a supervisor is required to have monitoring acess of all user mailboxes.

We are talking of adding around thirty additional mailboxes.

Subsequently following the removal of these additional mailboxes this allows access to Public Folders once more getting faster and faster each time a mailbox is removed from the Outlook 2010 folder list.

This only seems to be an issue in Outlook 2010, Outlook 2007 and Outlook 2003 do not seem to be similarly affected.

Does anyone know why this is happening ?

The Public Folders is seemingly placed in alphabetical oder in amongst all the other mailboxes in the folder list in Outlook 2010, whereas it appears as a seperate entity at the bottom of the folder list in Outlook 2007 and Outlook 2003.

Could this be something to do with it ?

Sembee [MVP]

How are you adding these additional mailboxes?

Outlook 2010 added a new way, using the new account method, which means you can connect to two different forests. That means the public folders. As users can have their own read/unread status, this means you will get the additional public folder trees.
Furthermore, each account has its own OST file, and if public folders are added to favourites and the client is configured to make public folders offline, then the hard disk is going to be thrashed as each account is going to be downloading its own copy of the public folder data.

Opening that number of mailboxes is not really something that Outlook is designed to do, and I wouldn't be surprised that performance is hit. A better method would be to use OWA or an archiving product through journaling.


Simon Butler, Exchange MVP
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Hi Simon,

I appreciate your comments and will check this out.. I've added the extra mailboxes the same way at we do with Outlook 2007 and 2003 under the Advanced > Open these additonal mailboxes tab.. they don't want to send anything from these mailboxes, just look at what is in them.

I've had a go with adding extra functional mailboxes and this is very cool and about time.

But it still remains that they'll want to do what they are doing the same way that they have always done...and it always worked perfectly well in Outlook 2007 and 2003..and still does..

We have the caching turned off..perhaps we actually need to trun it on and wait for it to complete ?

There isn't much stuff in the public folders, just a couple of calendars and a contacts folder that's all.

I've told them that this might be an issue with Outlook 2010 and that it may not have been designed to work like this.

All I get in response is " So they've made it worse then..like everything else of late"

Ho hum..

What I'm looking for really is for somone who knows that this is expected or known behaviour if you try to do this in Outlook 2010 because they have changed the way the folders are added viewed and cached.

If this is the case then they'll most likely want to revert back to Office 2007, they have a volume licence which permits them to do this..

I'll do some more investigation and see if this is OS related at all or has a bearing on it.

Be interested to hear from anyone else experiencing a similar thing.


Sembee [MVP]

You are pushing the extremes of Outlook. I don't think I have ever seen that many mailboxes opened in Outlook before. I don't even know if it is a scenario that Microsoft test.

Therefore it may well be that you have to downgrade because of the changes - simply because you are using Outlook in a way that is not usual.


Simon Butler, Exchange MVP
Blog | Exchange Resources