Lets find out which version of Outlook our users are running prior to upgrading to Exchange 2013.

So the easy and obvious choice would be Get-LogonStatistics which has information about client and version.

Get-Mailbox|Get-LogonStatistics|Group-Object ClientVersion
Count Name
158 3586.0.33110.2

But hey what… What is that version.. Thats not office.. Whats happening..

Lets just watch a single object..

ClientMode : ExchangeServer
ClientName : testexchange
ClientVersion : 3586.0.33110.2

According to social technet it got broken with a servicepack. I have seen 3584.0.33462.0 reported.

I found that microsoft has somehow mangled Get-LogonStatistics to only show a single version..

I still needed to find which version of Outlook that has accessed the Exchange server in the last week prior to migrating to Exchange 2013.

Lets turn to RCP Client Access Logging and see what we can find out

#Lets start by designing the default path
$Loggingpath = 'C:\Program Files\Microsoft\Exchange Server\V14\Logging\RPC Client Access'
#Lets select the last 7 days of logs.. Im not up at 2am, I guess are not either.
$LogFiles = Get-ChildItem $Loggingpath|Where-Object {$_.LastWriteTime -ge (Get-Date).AddDays(-8)}
#Lets read the good parts for each file and save them for a second.
$TheLogs = $LogFiles | ForEach {Get-Content $_.FullName}| Where-Object {$_ -notlike '#*'}
#Now lets convert them into something useful
#yea yea.. Its a long one, its available on the top of each logfile if you need to copy it..
$ConvertedLogs = $TheLogs |ConvertFrom-Csv -Header date-time,session-id,seq-number,client-name,organization-info,client-software,client-software-version,client-mode,client-ip,server-ip,protocol,application-id,operation,rpc-status,processing-time,operation-specific,failures
#Now for the magic
$ConvertedLogs | Where-Object {$_.'client-software' -eq 'OUTLOOK.EXE'}|group client-software-version
Count Name
65253 14.0.6131.5002
30159 15.0.4420.1017
4001 14.0.4760.1000
6168 11.0.8303.0
540 14.0.6117.5001
845 14.0.6109.5000
1250 15.0.4517.1504
194 15.0.4517.1003
53 11.0.8161.0
8 12.0.6672.5000
44 14.0.6025.1000
32 12.0.4518.1014

So there we have it.. We have lots of Outlook 2003 and cant migrate :(