Exchange and Cache Mode

[Zew]

Hey all,

I came across an odd issue the other day. Let me explain;

1) Administration User recently complaining that they no longer receive a notification number next to an inbox for an attached mailbox.
My first inclination was to remove and re-add the additional mailbox, via the regular way -> File -> Account Settings -> Change Settings -> Advanced -> Additional Mailboxes.
To my amazement it was not there, I decided to add it (Even though it was already on the left navigation tree of outlook. When I did this there were now two entries in the left navigation for the specified mailbox.
I also noticed cache mode was enabled. Now regularly most people always seem to say you really should have cache mode enabled. I however have found I seem to get numerous oddities and problems whenever cache mode is enabled.
First thing to note, we only have around 35 users, with an average mailbox quota of 2 gigs. Users also almost never work remotely, they are generally always on site and hardwired. For these reason I found disabling cache mode reduced the amount of issues (E.G Folders not being able to be deleted, or moved, or emails not being able to be moved from one folder to another, etc.) and now including this issue. The issue was when I disabled this users settings for cache mode the following happened:

A) Out look had to be restarted, when it did there was only one mailbox option in the left navigation tree (as I wanted) and the notifications for the inbox worked without an issue.

Great I thought I had solved the issue until!

B) The user claimed she had some emails missing from her "Sent Items". After some further investigation it turned out they were actually "scheduled emails". Emails that have been created and set to send at a later date. To which they should have been in the Outbox folder of her mailbox. It apparently was not.

I decided to go into my backups. This is where my question comes in.

To my amazement there was no backup of these emails in any of my backup points (I make up to 2 per day and keep a full two weeks on site, then have retention jobs via a BCJ) The person mentioned they created it a couple weeks to months ago. I created a delayed email, and then I went to check my backups today, and sure enough my scheduled email was indeed in my backup!

Does anyone else know if this is normal for mailbox's with cache mode enabled? or is my Exchange just right buggered up??

[Mike Resseler]

Hi,

From what I can read here, and applying some logic, it seems that Veeam is doing what it needs to do and those emails are not in Exchange. If you still have a user with cached mode enabled, let him / her open OWA to see if those emails are there or not. But since you disabled cached mode for user(s) and those emails are not showing up I believe they won't be there at all.

That obviously means there is something that is not right. If those scheduled emails don't appear in the sent items on Exchange it means that there is probably something wrong with your setup on those. I cannot remember any case from all the years I used Exchange and scheduled emails that they don't appear in the sent items. My advice here would be to log a support call with MSFT (or your MSFT partner) and dive into it to figure out why they are not appearing

My 2 cents
Mike

[Zew]

Hey Mike,

Yeah, def seems messed. All I know is that I took over this enviro a couple years ago and it was managed by a pretty unqualified individual. AFAIK this placed used to run Exchange 2007 and had a external managed service company do the migration to 2010. The documentation was horrible, and didn't outline a single step performed.

I'm currently doing the biggest project this place has have seen (A whole new domain). This will include moving to Exchange 2016, I'll just live with the setup as is with its little gremlins and start fresh in the new domain with proper documentation.

But as far as you know Cache mode is always a good thing? Just from this setup I found it caused a lot of issues, but as I mentioned I'm not sure exactly how the migration was handled.

[Mike Resseler]

I like cached mode. I am offline quite a lot, not to mention in 'great' hotels with 'fantastic' WiFi . Cached mode never has given me any issues at all. Plus it saves on bandwidth which is extremely interesting in my case

Never believe, always test yourself but I am convinced that Ex 2016 and cached mode of Outlook 2016 won't give you any issues in that new project

Good luck! And of course, don't forget to protect that new environment with Veeam

[Zew]

I'm assuming since you state you are mobile often, do you use an exchange edge server of some kind besides active sync? or behind a VPN in these cases?

In my place generally mailboxes are quota-ed low and users barely work remotely, when they do it is over a VPN, so no edge services (besides what we have setup for active-sync for mobile phones).

This is why usually disabling cache mode hasn't been a huge issue, since we our users usually have amazing bandwidth.

Oh of course, I love Veeam! Best Backup product I've ever used. I'm amazed they still have "On-Demand Sandbox"... really just a sure backup job, but I found with a setup that requires a fair amount of dependent servers (I.E SharePoint) even with a decent vPowerNFS store startup times and performance take a huge hit.