The mail DB will not mount:
Couldn’t mount the database that you specified. Specified database: DB1; Error code: An Active Manager operation failed with a transient error. Please retry the operation. Error: A transient error occurred during discovery of the database availability group topology. Error: Database action failed with transient error. Error: A transient error occurred during a database operation. Error: MapiExceptionJetErrorOutOfMemory: Unable to mount database.
There is a error in reading the memory of the hyper-v vm its memory in the vm was in GB but it does not see it correctly in MB's