Unable to connect to the Logical Disk Manager service

My initial thoughts to the 'without a reboot' bit is no! 2003's disk management can be a bit temprimental at times (We had a 2003 (32-bit!) file server with approx 35 SAN LUNs and many connected users. We had the occasional issue with expansions, and even seeing new LUNs.

For most reliability, we did the following procedure:

  1. expand SAN LUN using SAN tools
  2. open Device Manager and in the menu, click on Scan for hardware changes
  3. Log out
  4. Log back in
  5. Open Disk Manager and check for new LUN / free space (Sometimes requires a scan for disks)
  6. Extend using Disk Manager GUI or diskpart

So try logging out and back in, it may do the trick but I would guess not seeing as your disk management service is not startable.

Check to see if you have the following hotfix (I'd guess you're fully up to date already, seeing as it is an older O/S) - http://support.microsoft.com/kb/957271

if not, try applying the above.