A lot of customers have looked at archiving solutions for Exchange over the last few years, and the most common reason for doing so is to reduce the volume of data held on the Exchange server. This obviously brings benefits for the administrators – they don’t need to back so much “stuff” up every night, and they have a chance to use the archive for longer term compliance/discovery purposes. I’ve even seen customers using archives as a way of migrating content from another email system – eg company migrating from Novell Groupwise to Microsoft Exchange decides they would just bung all the Groupwise content into an archive so they can start with nice clean mailboxes on Exchange, but the users don’t lose access to their historical data.

Archiving does pose an interesting question, though – what if you’re just archiving all the garbage that people don’t delete? I’ve seen cases of companies who have an archival solution but have implemented no mailbox quotas, on the basis that the archive takes care of handling everything they don’t want to back up every day. Now this, to me, seems like a situation where the Exchange mailbox stores are going to be relatively static, but the archives are just going to grow indefinitely…

Exchange 2007 Managed Folders

There are some good papers and demos here on Managed Folders in Exchange 2007, and if used appropriately these capabilities could provide a decent alternative to archiving altogether, or could at least provide a way of throttling the amount of junk that ends up in the archive. A nice side effect is that “important” mail is kept online on the server, so is always accessible from any client (without needing to put additional plug-ins or install any other archive-aware software) such as OWA or even mobile devices.

I say this with some personal experience, since I’ve been using Managed Folders for a while now, in the real world. My mailbox sits in the Exchange Dogfood environment where the Exchange development group and Microsoft IT get to implement very early technology before it’s finished, and before it gets rolled out to everyone else in MS, let alone our customers. My mailbox was on Exchange “12” for a year before it released, and it is set to a gut-busting 2Gb quota, so I don’t really need to use PST files any more.

The approach to using managed folders is one where all mailbox content (and it’s possible to differentiate different types – eg having different rules for emails, calendar appointments, voicemail etc) would have some age limit set (eg 6 months), and on expiry of that time, the content gets “dealt with”. This could involve deleting the content, forwarding it somewhere (through journaling, perhaps sending to a different mail system, to a Sharepoint 2007 site, etc), or moving it from the main mailbox folder into one of the managed folders…

 These managed folders are defined on the server and applied to the user via a policy (so that users in different departments might see different folders from others), but it’s important to note that they are mailbox folders (ie they appear as regular-ish folders within the user’s mailbox, are only visible to the same people that might be able to see the mailbox itself – ie they’re not public folders of any sort -and count against the mailbox quota).

Retention limits can be set on both the “regular” mailbox folders (such that after 6 months, everything will get shifted into one of the managed folders), and also on the managed folders themselves… so in this example, everything from the Inbox etc would get shoved into the Cleanup Review managed folder, and after 30 days in there it will be deleted from the server. So the onus is now on the user to decide if they want to keep anything in that managed folder, and if so, move it to one of the other managed folders, which will typically have a longer retention period (eg HR records might be kept for 7 years).

I’d liken this approach to pushing the user into deciding what they need to keep, and basically assuming that anything which doesn’t get specifically tagged or categorised by the act of moving them to the correct place, is therefore assumed to be disposable and can be removed from the server. Of course, it could still be archived somewhere else for long-term storage. It’s a bit like when I was a kid – my mother would periodically come into my room and put anything left lying around into a bin bag and threaten to chuck it out… if I protested, she would retort “Well, if you wanted to keep it, you shouldn’t have left it lying on the floor now, should you??”

//E

Following on from my recent post about search folders, I got a few questions and comments via mail. One, from Christian, asked if it was possible to use a search folder to filter out only mail which came from “outside” – eg Only show me the last day’s mail from external senders, thus filtering out all the organisational spam that will typically be clogging the mailbox.

I had a bit of a scratch of the old bonce, and figured out one possible way – there may be others, but none are really obvious. There are a couple of requirements for this to work out, though…

• Your inbound mail must be handled by Exchange 2003 or 2007, using the Intelligent Message Filter technology to stamp inbound mail with a Spam Confidence Level value. It may be possible to use other tools which also support the Exchange Anti-Spam Framework.
• You need to install a form into Outlook, which will expose that SCL property which is stamped onto inbound mail. This will then allow you to add the SCL value to views, filters etc.

Once you’ve got the SCL form installed, you can create a search folder with the appropriate length filter (eg all mail since yesterday morning, as described on my previous post) and add a new filter to restrict the SCL value (click on the Field drop-down, and look for either the name you gave the SCL form, or the “Forms…” link to add that).

If you set the filter to be at least “0”, that means that any message with an SCL value of 0 or higher will be shown (you might want to add an additional filter to not show stuff with a high SCL value, since they’re lkely to be in your junk mail folder anyway). You could also restrict which folders are shown, based on the same logic in my earlier post.

Anyway, mail with an SCL value will have come from an external source (ie internal Exchange<->Exchange mail won’t have been scanned by the IMF at all), and will have come from an anonymous connection (mail sent by authenticated servers through the same gateway will be assigned an SCL of -1 to show that it’s exempt from filtering by the SmartScreen logic within the IMF).

It might take a little while to render the search folder if you’ve a large mailbox, but it does provide a nice way of showing you only stuff which came from outside.

//Ewan

In the default modus operandi, Outlook 2007 likes to be in cached mode when running against Exchange, which is generally a *good thing*. Cached mode means there are (by and large) fewer occasions to go back & forth to the server, as it operates by synchronizing a local copy of the mailbox down to the OST file on the client. This means that operations such as content indexing (which Outlook now does by default), sorting, filtering etc, all happen on the client rather than hammering the server.

Outlook 2003 did this too, but 2007 offers a new capability in caching the calendars of other users on your behalf. Now that’s generally a good thing too – it means that when you open someone’s calendar in Outlook, it adds that user’s calendar to your cache so that you can see it when offline, and if it’s someone you regularly snoop on (let’s face it, a lot of calendar lookups are just checking what people are up to, aren’t they?), then it will be quicker in opening the calendar in future, since Outlook doesn’t have to go back to the server for everything.

A possible downside to this is if you’re in a large organization and you routinely (but occasionally) open lots of people’s calendars – what then happens is that Outlook spends time and increases the size of your OST by dragging everything down to your PC.

There are a couple of options to mitigate this potentially unwanted behaviour:

• Remove unwanted calendars from your list. If you go into the Calendar in Outlook, you might see a large list of “People’s Calendars”, meaning you’ve viewed them before. You could right-click on each individual calendar on the list and choose “Remove …” and it will ditch that item from your list and also stop synchronizing it (assuming you want to continue synching some other calendars), or…
  
• Go to Tools | Account Settings | double-click on <Exchange Server account> | More Settings | Advanced  and clear the check-box which says “Download shared folders…”

If you’re experiencing problems with excessive calendar synch traffic, one of these options might sort you out…

//Ewan