Hi,
Our Hybrid environment Detail.
Exchange2010 on-premises with sp3
ADFS and dir.-sync
Our most of users move exchange online o365.

Today our exchange on-premises database drive almost full, total drive size 170GB, Used space 169GB free space 800MB... i run this command and check mailbox database size status.

----------------------------------------------------------------------------

[PS] C:\>get-mailboxdatabase -status | fl DatabaseSize
DatabaseSize : 10.94 GB (11,751,194,624 bytes)
DatabaseSize : 24.06 MB (25,231,360 bytes)

----------------------------------------------------------------------------

I check the exchange 2010 installation folder size in  program files.... here is the detail.

----------------------------------------------------------

D:\Program Files\Microsoft\Exchange Server\V14\Mailbox\Mailbox Database 1184766598

Total Size== 134GB

in this path there is lot of 1MB size TEXT file like this name E000004EDD6-----which total space is 123GB

----------------------------------------------------------

D:\Program Files\Microsoft\Exchange Server\V14\Mailbox\Archive Database

Total Size= 26GB

We recently move our ex-employee users exchange online to on-premises and export mailbox user data, and then delete that users on exchange2010 server, but space side no effect,

Please advice what is the best solution without any downtime/mess the server.

Regards,

Hello,

Even though you move your mailbox, there will be soft deletes the mailbox on the source database.

After you delete these users, there will be retention policy for these mailboxes.

So I recommend you use windows server backup or Microsoft System Center Data Protection Manager to do full backup for your database on schedule to free your disk sapce.

Hello!

Maybe this will be helpful http://exchangeserverpro.com/exchange-2010-faq-disk-filling-log-files/ 

I absolutely agree with cara chen, You have to do full backup of your MailboxDatabase or enable circular logging http://blog.mattsampson.net/index.php/circular_logging_exchange_2010?blog=1

HI,

Thanks all for the reply,

issue resolved now, windows server backup give me lot error.

then I use Microsoft System Center Data Protection and after backup DB the log shrink and issue resolved.

Regards,