Recently had a customer migrating to Office 365 that had a large and diverse user population that was unfortunately not in a managed desktop scenario.
After reading several other sources on how to collect this data from the RPC/HTTPS logs on the Exchange CAS server, I did some hunting on how to best collect this data. Luckily, I was able to find this here (thanks to Nate-N8!)
"C:\Program Files (x86)\Log Parser 2.2\logparser.exe" "SELECT TO_LOWERCASE(EXTRACT_SUFFIX(client-name,0,'=')) as User,client-software as Software,client-software-version as Version,client-mode as Mode,client-ip as IP,protocol as Protocol INTO c:\ClientInfo.csv from 'd:\temp\RPC logs\exchcas01\RCA_*.log','d:\temp\RPC logs\exchcas01\*.log' GROUP BY User,Software,Version,Mode,IP,Protocol ORDER BY User" -nSkipLines:4 -i:CSV -o:csv
This generated a CSV file, which I was then able to load into Excel and utilize a sorting and grouping to then show Outlook versions and frequency of connections. This was a sample set of 7 days. Best of all, you can expand from here and see the actual users impacted so that you can plan and target your Office/Outlook desktop upgrades!
And for handy reference, here are the listings of Office/Outlook versions:
Pre Outlook 2007: http://support.microsoft.com/kb/870929
Outlook 2010: http://support.microsoft.com/kb/2687455
Outlook 2013: http://support.microsoft.com/kb/2817430 (SP1 is 15.0.4569.1506, RTM is 15.0.4420.xxx)
Generally, for the best Office 365 experience, I recommend being on at LEAST Office 2010 SP2 (14.0.7015.1000) or higher.
Once you have the generated CSV, you can follow these instructions to manipulate the data!
To do the same thing (only better) with MAPI over HTTPS, check out my article here: