Extend System Partition on a Windows Server 2003 VM using Dell ExtPart

There is no native tool that enables extending system partitions (C:\ drives) on Server 2003. There are multiple ways to perform this task, however, the only method that can be done onlineutilises a Dell utility called ExtPart. It can perform the extension of the system partition with no downtime although sometimes booting into Safe Mode and then running ExtPart is necessary to clear locks on the disk.

Note: This applies to Server 2003 only, newer versions of Windows do not suffer from this limitation, Disk Management as well as the diskpart are able to extend system partitions on-the-fly.

The first step is to download the ExtPart utility from this link. Click on the Download File link and save it to your desktop. The file is a self-extracting zip file called ExtPart.exe

Double-click on it and accept the default path it will extract the utility to:

Click on Unzip and the files will be extracted successfully

To demonstrate how useful ExtPart is we will use an example whereby our demo VM has a 15 GB C:\ drive and it needs to be increased to 30 GB. A screenshot of the the current state of the C:\ drive is below:

We go into the VM settings and can see that the virtual disk is indeed 15 GB in size:

We increase the virtual disk size to 30 GB and apply the change:

Within the VM load Disk Management and select Action > Rescan Disks so that the system sees the newly added 15 GB of storage:

After the re-scan completes you will now see the extra 15 GB of unallocated space:

Now we need to run the ExtPart utility expand the C:\ drive so that it utilizes the 15 GB of unallocated space. To proceed, open the command prompt and go to the location where you extracted the ExtPart utility, in my case, C:\dell\ExtPart:

Then run ExtPart.exe:

Enter the volume that is being expanded, in this example it is the C:\ drive so enter just C: without the backslash:

Then enter the amount in MB to increase the volume by, I entered 15343:

The output will confirm the new size of the volume (C:\ drive), which is 30678 MB:

The full sequence of commands can be seen in the screenshot below:

When going back into Disk Management and re-scanning the disks, we can see that there is still 31 MB that is unallocated:

To add that remaining 31 MB to the C:\ drive, we go back to ExtPart and perform the same series of steps but this time add 31 MB:

A screenshot of those steps is below:

Now going back into Disk Management you can see that the C:\ drive is using all of the provisioned space in the disk:

If the utility returns an error such as “the disk is not accessible” or “unable to connect to C:” then reboot the VM into Safe Mode and then run the same ExtPart commands. This is caused by various services locking the disk and preventing ExtPart from extending the volume. Booting into Safe Mode starts up the OS in a clean state, so only minimal services and drivers will run, thereby allowing ExtPart to expand the volume without interruption.

Credit to http://www.vsysad.com/2014/02/extend-system-partition-on-a-windows-server-2003-vm-using-dell-extpart/