How to extend system partition on Hyper-V Windows Server 2003 VM

9:55 am in Hyper-V, scvmm, win2003 by Wim Matthyssen


Last month, I worked at a customer who had a problem with low disk space on the system partition (C: drive) of a Virtual Machine (VM) runnig Windows Server 2003 as operating system. He received the “Low Disk Space” alert and wasn’t able to defragment or install any new software. He was also concerned that whitout enoug space for the system, the server would not work efficiently and stable. So in my first blog post I will explain how I fixed this.

First of all, you need to expand the virtual hard disk (VHD) of the VM. In the post I will use System Center Virtual Machine Manager 2012 R2 (SCVMM) but you can also do this from the Hyper-V manager. To fix this issue you need to go trough the following steps:

1) Shutdown the VM

2) Open Properties of the stopped VM

3) Go to Hardware Configuration and locate the disk in question

4) Select Expand virtual hard disk (GB): and enter the new size

5) Click OK


6) In the job window you will see following action:


7) If the job is all done, start up the VM.

8) When the VM is started, open Run and type in following command diskmgmt.msc to open Disk Management

9) Click OK


The problem that you face at this point is that because it’s a Windows Server 2003 you can’t use “Disk Management” to extend the system disk with the 8 GB unallocated space. Like you can see in the screenshot below the option “Extend Volume” isn’t available.


10) So to expand the SYSTEM disk we will use a tool called Dell ExtPart Utility. You can download it from here

11) Save the zip file to a folder (like example Temp) and extract it. I’ve extracted it to the folder C:\Dell\Expart

12) Next open a Command Prompt and go to the above folder

13) Type in the command extpart “drive:” “size to extend”. In my example this is extpart c: 8192

14) Click Enter


15) Now if we open up Disk Management again, you can see the system drive has a size of 20 GB instead of the 12 GB from before. After the extend, the previously unallocated space has been combined with the system drive to form a single larger drive. In the end the extra space is available to install new software or install Windows Updates. Also the server will run stable again.


This concludes my first blog post. I hope it’s a fine start and that you will keep following me. So keep tuned and I’ll be back soon.