The process of increasing the system drive, or C: drive, of a Windows 2000 or 2003 VM is very straight forward. One item to keep in mind is that the VM in question needs to be shutdown, and the virtual hard disk needs to be mounted to a different (helper) VM. Here are the steps for increasing the C: Drive on <strong>VM1</strong> from 10 GB to 25 GB. We'll use <strong>HELPERVM</strong> to complete the job:

 
<ol>
	<li>Shutdown <strong>VM1</strong>, that needs the C: increased (be sure to note where the virtual hard disk one is stored – local storage, iSCI lun, SAN, etc)</li>
	<li>Go to Edit Settings and change the virtual hard disk size to 25 GB, and click OK</li>
	<li>Close out of this <strong>VM1</strong>, and go to the <strong>HELPERVM</strong></li>
	<li>Edit the settings of the <strong>HELPERVM</strong> and add the virtual hard from VM1 – just browse the datastore locate the hard drive and add it</li>
	<li>Once the hard disk is added, log into the helper <strong>HELPERVM</strong></li>
	<li>Go to Disk Management and rescan the disks, you will see the C: drive from <strong>VM1 </strong>in the lower pane</li>
	<li>You should see the original size, plus you see the additional 15 GB as "unpartitioned"</li>
	<li>Right click on the 10GB drive and click extend, follow the wizard the drive will take up the entire space that has been allocated</li>
	<li>With the drive now showing up as the entire space, in this case 25 GB, we need to remove it from the <strong>HELPERVM</strong> – TO DO THIS WE NEED TO SHUTDOWN THE <strong>HELPERVM</strong></li>
	<li>Shutdown the <strong>HELPERVM</strong>, edit the settings and remove the hard drive</li>
	<li>With the virtual hard disk disconnected from <strong>HELPERVM</strong>, we can go back to <strong>VM1</strong> and power it up,</li>
	<li>Navigate to disk management and rescan the disks – You should see the 25 GB hard drive now for C:</li>
	<li>You will probably need to reboot VM1 one more time as Windows will recognize the change</li>
</ol>
Now you're all set with a bigger C: Drive.