If you need to backup exchange without having to shutdown the information store you can use the below script to backup the exchange database.
Please note that this backup will also do a rolling backup adding the week day to the backup file so you will need upto 7 times the Database size on your backup device.
NOTE: This backup sends the NT Backup.log and then deletes it. If any other NT backups are running on the server then this will create a problem with the backups logs.
Extra Files required.
You will need a copy of sendemail.exe that need to be located at %adminitpath%\programs
You will also need to create a ntbackup .bks file and save to D:\Data\AdminIT\Scripts\Exch_SysState.bks (You can remove systemstate but it is suggest this is keeped.)
“JET <Server Name>\Microsoft Information Store\First Storage Group\