Tech Blog

So had a bunch of errors on my Exchange 2010 server today, namely:

Event ID 9646 MSExchangeIS

Mapi session "cd83bc42-1bff-459e-9db2-558cc68478b9" exceeded the maximum of 500 objects of type "objtFolder".

The error doesn’t give much away but basically what its saying is:

A user with GUID “ccd83bc42-1bff-459e-9db2-558cc68478b9” has more than 500 open folders in a single session, because exchange only allows 500 open folder connections (for a cached mailed) at a time its going to screw with the user and in our case not automatically update the users folders in Outlook 2010.  Please note this is different from open MAPI connections to the mailbox.

Note this has been edited with help from Mark Daley who stated:

the objtfolder is an ‘Open Item Limit’ ie the limit of the number of folders that are being opened in a single session, not the number of connections being made to the mailbox which is a session limit See (http://technet.microsoft.com/en-us/library/ff477612(v=exchg.141).aspx). This limit is the total for the session so if a user has 250 folders in their own mailbox and say 300 in a shared mailbox then the limit will be breached. The other thing that should be explained in that this is only likely to occur when the mailboxes are cached (shared and non-shared) as it is the consequence of caching that is causing the limit to be breached because each folder is opened / counted during the mailbox sync process. Therefore turning off caching mode for either the primary mailbox or just the shared mailbox is another fix for this issue.

You may be wondering how a user could have more than 500 connections, well in our case the user had two mailboxes attached to their own mailbox and all the folders (inbox, outbox etc) together added up to more than 500 folders.

You can scan a mailbox with Power Shell to determine the number of folders:

Get-MailboxFolderStatistics USER1@BohemianGrove.co.uk | Sort-Object ItemsInFolder -Descending | ft Name, FolderPath > C:\temp\countFolders.csv

So lets say you see the errors on your Exchange 2010 server but don’t know who’s having the issue, you find Users MAPI GUID’s by running the following Power Shell command:

get-mailbox -Resultsize Unlimited | ft Name,ExchangeGuid -AutoSize > c:\temp\msExchMailboxGuid.txt

Once you know who the user is what can you do, well there’s four options in my mind:

1) Tell the user to re-organise the folder structure,

2) Remove some of the extra Mailboxes from a users mail profile if possible (you could add a extra profiles to Outlook, making Outlook prompt on start up),

3) Do not cache the mailbox in Outlook or simply do not cache the additional mailbox in Outlook.

4) Change Exchange 2010 to allow more than 500 folder to be open at a single time for cached mailboxes!

To proceed with 4) you’d need to do the below but be warned if large quantities of users connected with plus of 500 folders your server performance will suffer drastically:

Log onto all your mailbox servers and create the following registry key:

1. Click Start, click Run, type regedit, and then click OK.
2. Expand the following registry subkey:
   \\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem
3. Right-click ParametersSystem, point to New, and then click Key.
4. Type MaxObjsPerMapiSession, and then press ENTER to name the new sub key.
5. Right-click MaxObjsPerMapiSession, click New, and then click DWORD Value.
6. Enter the object type as specified in the event description, and then press ENTER.
7. Right-click the object type that you entered, and then click Modify.
8. In the Value data box, type the number of objects to which you want to limit this entry, and then click OK.

Did you know you can automatically assign calendar entries colours (notice how colours is spelt the correct British way) and categories.

I.e. say you have set a meeting called “Project Bob” and that meeting and any future meeting with words “Project” and “Bob” in to be set a specific colour in your calendar, well here’s how:

Open your Outlook Calendar

Click the View Menu item

Click the “View Settings” button under Current View

Click the “Conditional Formatting” button

Click the “Add” button to create a new rule for auto-colouring appointments

Enter the name of the rule in the “Name:” text box e.g. Project Bob

Select a colour in the “Colour:” drop down list box (I like green)

Click the “Condition…” button to identify the conditions under which this colour should be applied

Select the “Appointments and Meetings” tab and enter a keyword into the “Search for the word(s):” text box to look for a word in the Subject field

Click OK to all screens,

You should see the changes straight away.

Just a quick post on how to scan PST (or OST’s) files if they become corrupt or wont open:

The tool I’ll use is ScanPST.exe which is installed when you install Office 2010.

ScanPST.exe is located below with Office 2010:

C:\Program Files (x86)\Microsoft Office\Office14\SCANPST.EXE

Open the tool and click Browse and find the PST you want to scan:

Then click Start, if the PST is large this can take a while:

If the PST can be fixed ScanPST will prompt you to backup it up before it attempts to fix it:

Click Repair.

That’s it done.  Try and open the PST or OST again from Outlook.

If the above didn’t work and I wouldnt be surprised if it doesn’t you could try Stella Phoenix PST report tool which is better and generally works!!

I had a replace a PC for a user today who’s email was hosted externally.

So after I replaced the PC I came to setup Outlook, checked the old PC and saw the following setup:

What on earth is

iC Exchange I think to myself!! Check the config:

What are these settings, I’ve never seen the like before!!!

So what do I do?!?  Well the Server must be accessible from the internet so after a bit of playing the server was accessible from http://mail.EXCHAGESERVER.co.uk and using some provided credentials I could logon!!

Once I logged on I realised I wasn’t looking at Exchange I was look at VMware Zimbra!!  I’ve never heard of this and watching the promotional video they said Exchange was legacy so I immediately decided they were stupid!!

Well reading about I found I needed a Outlook connector which I could download from any server running VMware Zimbra!!

So went to:  http://mail.EXCHAGESERVER.co.uk/Downloads/

Downloaded the client, installed and used some provided credentials!! BAM done.

As we used to use some awful hosted Exchange 2003 platform we decided the first thing to be moved was Exchange…. So as all the users were on a separate domain we created a lavish Exchange 2010 platform and used linked mailboxes for everyone and migrated the mail!! Think I posted on how we did this earlier…basically created the linked mailboxes via PowerShell and a CSV file then ExMerge the mail out of Exchange 2003 and used a PowerShell import command to pull the mail in (although you could use new PST Capture tool now to import which provides a pretty GUI).

So here we are, linked mailboxes as far as the eye can see, full of crappy mail!

Next we setup Auto Discover on all our domains to point to exchange and bobs your uncle.

So, everyone is working away…and suddenly people start complaining they keep getting prompted for their username and password credentials  in Outlook 2010 running Windows 7!

Ok I think, you’d expect it once or twice due to going cross domain but not 20 or 30 times!!

The Fix, after trying everything we discovered it was down to AutoDiscover and it not being routed internally!

Added it (it being AutoDiscover.Domain.com) to the proxy exclusion list in IE and wham! No more prompts!