We migrated from EX2010 to 2016 last year.

New databases created etc., mailboxes migrated.

I had to turn up the quotas for some DBs, otherwise I couldn't migrate large mailboxes in.

Unfortunately, I neglected to straighten the quotas across all DBs later...

Normally, I assume that the mailboxes either have "Use default quota setting of the mailbox database" set, or that individual quotas have been defined for each mailbox.

Hence the question:

- What happens to a mailbox that has the "Default database account settings" activated?

e.g. mailbox size 350 MB, standard quota database-wide "Warning from 500MB", send up to "550MB"

Now I set the warning "from 250MB" at database level, sending possible up to "300MB"

Can the named user then still send emails, or do I have to make do with Excel evaluations etc. and do this individually later?

Or does the setting of the database-wide setting only apply to NEW POSTBOXES, or mailboxes migrated to the DB? (Which would be my preference)