Lab 2, make sure CL1 can access the internet. LON-EX1 and LON-EX2 have two exchange services not working, need to reset the password on those two accounts.
Lab 5 A Exercise 1 Task 1 Step 4 create DNS entry of "mail" not "E-Mail"
Lab 5 A Exercise 2 Task 2 Step 1 enter "Notepad" not "Editor"
Lab 5 B Exercise 2 Task 2 Offline access does not work
Lab 6 Exercise 1 Task 2 Step 8 if the Content Index is FailedAndSuspended try
Update-MailboxDatabaseCopy
"Mailbox Database 1
\LON-EX2"
-CatalogOnly
see https://www.frankysweb.de/exchange-20132016-index-neu-erstellen/