Built a new Exchange 2003 SP2 server (Windows 2003 OS).
Moved about 20 GB of mailboxes to this server over the past three days.
Drive C houses the operating system. 65GB total space (RAID 1).
Drive E houses the Exchange mail database. 205 GB total available (RAID 5).
Got a message saying that disk space on drive C was very low. Down to about 20 MB.
Also found that Cisvc.exe was utilitzing 10% of the CPU capacity pretty consistently.
Deleted exchange log files and was able to get back up to about 30 GB of free space on C.
Drive space on C continued to disappear. Stopped and disabled the Indexing Service (noticed that it had been disabled on my other Exchange server). Disk space loss has since stopped.
So what is occupying the missing 20 GB or so of disk space and how do I get it back?