I have 2-3 DCs in my virtual lab and at a given point of time some of them might be off. This confuses the Exchange Management Console (EMC) though and it throws errors like these: “An error caused a change in the current set of domain controllers. It was running the command …”
I wouldn’t mind if the error went off after I clicked OK and things continue to work, but they don’t. Running the cmdlet show in the EMS works though so obviously the problem is with the EMC. Closing and re-opening the EMC doesn’t help either.
The fix for this is to clear the cached files of the EMC. Like every other Microsoft Management Console (MMC) the EMC too stores settings (such as the DC that was last used in this case) to speed up things, and so what happens is that when a DC that previously worked is now offline the EMC does not automatically try a new DC. Clear this cache and the EMC works well again.
To do this click on
Options in the EMC, and then “Delete Files” in the resulting window. You get a prompt to confirm, click “Yes” on that and now the EMC should work again.
Update: This doesn’t always seem to work. An alternative approach is to go to
C:\Users\AppData\Roaming\Microsoft\MMC on the machine where you are trying the EMC and delete the file called “Exchange Management Console”.