Does Exchange have ability to run hidden mailboxes?

Hello,

Title of my question may sound a little bit odd but I was thinking if Exchange 2010 or 2007 or any program that would work in conjunction with Exchange has ability to create this structure:

1. Users having their normal mailboxes connected and using them as everyone would in Outlook 2003/2007/2010.
2. Users having additional mailboxes (from old Exchange 2003) attached but hidden on demand of Administrator. For example administrator could easy disable them just like they never been attached making them invisible to users and everyone else. Would be good if such mailboxes could be easily removed out of system (lets say on external drive) by simple step not manual job for 100 mailboxes.
3. Users without ability to copy/move their mails to outside storage (like a local .pst file)?

Do you guys have any suggestions on this? I was thinking maybe using public folders but this seems like overkill and not really suited for this. And please don't ask me why I need this type of security (it's not something I requested).

Edit:

Full context. We have exchange 2003 now which is used over 2 years. It has limit of 2gb per mailbox now. My management is afraid that some people may have corresponded between themselves (internal mail) about stuff they are not allowed to share between departments. Since I won't go over 100 mailboxes and check whether such correspondence had place and delete those mails my management want me to find a way to delete (first archive on dvd) all emails before 31st march 2010 (basically leaving only last 3 months) in each mailbox. Kinda clean start.

After doing that I would be told to hand over archived mailboxes to users so they can use it when necessary but so the mails aren't on server. This really kills my idea of having nice Exchange server with lots of space and so users ability to work with history (I use my history emails all the time) gives them some additional pluses.

Idea of management is that when I hand over archived emails most people will use it only occasionally or never and it will be harder to track but I know this solution will blow up in my face some day.

So I would prefer some way to archive those emails and connect them as a second mailbox of some kind per each user and on demand i would be able to switch it on and off.

I want to upgrade to Exchange 2010 from SBS 2003 with Exchange 2003 and it's something that would convince my management to actually go for it. It doesn't have to be internal Exchange 2010 feature but maybe some kind of addon or so. I saw GFI Mail archiver but not sure if it has that ability.

From serverfault MadBoy

• Do they actually have to be physically removed? Could them not appearing in the address book be acceptable? There is a setting to "Hide from Exchange address lists". It is under the "Exchanged Advanced" tab in the user properties. It can be toggled at the admins discretion. Takes a little while to sync with everyone's Outlooks.

  Seems like you are doing this for security reasons so I don't know if its acceptable. But if users cannot find the mailboxes they wont know they exist. Security by obscurity....

  MadBoy : What I am looking for is option to hide it from the user that will be using it daily. For example he sees his old emails for 99 days and then one day I can just switch it off and switch it on after 50 days. It shouldn't generate errors for users in outlook saying something is missing etc. Just simply gone so that user can't use his old emails again. Kinda like archive on demand feature.
  From Campo

• If it's a one-time cut-off at the 3-months or older mark, you can achieve this by using exmerge to take all mail older than 3 months and dump it out to a PST for each user. You could then back these PSTs up, and either make them available to users on a network share (where you can add and remove the ability for a user to open the PST as you wish), or give the user a copy to load locally onto their machine (faster and less network space requirements, but you'll have no control over when the user can and can't access the PST.

  If you're looking to keep a constant 3-month retention period on users mail files, you could look at a solution like MailMarshal, or externally something like Postini or Messagelabs mail archiving features. You can couple that with an email policy that'll clear files older than 3 months out of everyone's mailbox.

  With all of the above options you can set read-only so that users can interact with the archive but not delete/alter old emails.

  MadBoy : Does it have ability to take away access with simple turn it off or so solution?

  Chris Thorpe : For postini, you can enable/disable user archive access on a per-user setting from the control panel. For the PSTs, you can grant and deny access with share or NTFS permissions as you would with any other file on the network.

  Chris Thorpe : BTW you could run some scripts against your mail stores to pull out the information that management requested about people in each department mailing each other. All you need from management is a candidate list of To: and From: users, and you can search the mailboxes for mails that meet that criteria. I've done this previously when management wanted a list of all mails Dave Smith sent to Jane Doe between 2nd May and 9th March, etc.

  MadBoy : As for NTFS solution problem is people would get errors in their Outlook which is not what I want (don't want to confuse users etc). I was reading about GFI Mail Archive and it looks okey, but i'll be checking other solutions as well.

  MadBoy : My management doesn't care if they did it (to punish them or something). They just want it gone. Problem is there could be a lot of conversation between departments that isn't problematic and only few issues can be. So all in all I or someone else would have to go thru emails and delete the problematic ones or archive them with some software and in case of 'control' be able to disable and unmount it like it never happened.
  From Chris Thorpe