Just came across this simple diagram of MS Exchange client-server protocols and figured I’d share it here. These days there is a bit of a confusion on where each protocol used in Exchange so I decided to try and fill this gap. I will also put it in the context of QMM migrations and describe how it evolved over the years plus point out a difference in permissions assignment model.
You may say that it’s not a migration related issue but I will disagree with you here because once you start having issues with your migration LAB, all your migration plans start falling apart… and here I am with my new blog. So imagine one day you start your VMs running on Windows 10 Hyper-V machine (Dell XPS15 laptop), right-click in Hyper-V Manager | Connect and instead of a friendly OS window it shows a half of a black screen, failing to initialize proper VM image. VM itself however runs fine under the covers and can be connected to via RDP, but in many cases where networking configuration is not cooperating or machine is not booting up, RDP access is not going to be much of a help here.
This case is another one of those countless issues which reminds you every day that no matter how long you have been doing migrations you can never rest on an old knowledge and experience. Rather you need to keep learning something new which may at first appear same old, that’s a nature of our job 🙂 Everyone have probably seen MAPI_E_FAILONEPROVIDER mailbox access error thousands of times and knows it may be caused by name resolution, permissions (mostly)… I have also seen some “exotic” cases where same LegacyExchangeDN was present on the proxyAddresses attribute of another recipient (Contact) preventing both Mail Sync Agent access and end user’s Outlook MAPI login. But I bet the one I am about to describe is not something you’d encounter often.
This one is quick but interesting. You may run into an error “WMI Provider Error: Cannot find object or property” during SQL Server migration, in particular when switching SQL Service account from Source to Target.