I eagerly installed the IMF into my production Exchange environment on the day it was released and unfortunately tripped over my own eagerness. I have 2 servers in a front/back-end setup and I applied SP1 to my front-end and installed IMF there and everything was okay and both installs went smoothly. My backend Server because I had clients connecting to it I wanted to wait until I could schedule an outage to apply SP1 so I didn't upgrade this straight away. Since the IMF installed okay and I couldn't find anything that told me I needed SP1 on all my Exchange servers I decided to turned it on and test it out. Well it worked "sort of" the SCL was being set fine on all the messages going though and my Back-End server was responding to this but instead of just junking all mail with the default SCL of 8 it was junking every email. Going back over all the doco I couldn't see any problems with my install so I put it down to not having SP1 on my Back-end Server. Last night I managed to get SP1 on my Back-End Server and this morning re-enabled the IMF and everything is now fine. The anti-spam Infrastructure has been around since the release of 2003 so I still find it a little weird that I had this problem but so far I like the IMF.
For the last couple of years the most constantly popular post by number of views on this blog has been Export calendar Items to a CSV file using EWS and Powershell closely followed by the contact exports scripts. It goes to show this is just a perennial issue that exists around Mail servers, I think the first VBS script I wrote to do this type of thing was late 90's against Exchange 5.5 using cdo 1.2. Now it's 2020 and if your running Office365 you should really be using the Microsoft Graph API to do this. So what I've done is create a PowerShell Module (and I made it a one file script for those that are more comfortable with that format) that's a port of the EWS script above that is so popular. This script uses the ADAL library for Modern Authentication (which if you grab the library from the PowerShell gallery will come down with the module). Most EWS properties map one to one with the Graph and the Graph actually provides better information on recurrences then...