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How To Increase size of a Boot Volume C: (VMDK) on Windows 2003 VM with No Downtime

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When your production Windows 2003 VM is running out of disk space on C: , and you must increase the space.  What do you do?  

This tutorial will show you how to increase the size of a virtual machine disk (VMDK) for boot volume C: on Windows 2003 (32 Bits) operating system with no downtime.

Disclaimer – Before you perform steps in this tutorial, it is always good idea to have a good backups.

Example:  Increase the size of a Windows 2003 C: Drive from 11GB to 12GB

1) Download Dell ExtPart utility -  Dell Extpart only works with 32 bit operating systems


2) Copy the ExtPart to the VM you would like to expand the disk, and extract the file to C:\Dell\ExtPart folder

3) On your ESX/ESXi Host, go to the VM you would like to expand -> Right click -> Edit Settings -> Hard Disk –> Virtual Disk

4) In Provisioned Size -> Type the space you would like to increase

Example:  Current size of the Virtual Disk is 11GB
Enter a brief description of your file (required) Increase Provisioned Size to 12GB
Enter a brief description of your file (required)5) Log on to the Windows 2003 VM as System Administrator. Open Disk Management
Enter a brief description of your file (required)
6) Select "Rescan disks" to detect the new space you added it to the VM if it’s not already shown. You will see the new 1GB of unallocated space
Enter a brief description of your file (required)7) Open Command Prompt and Go to c:\dell\ExtPart folder, type: extpart

8) In Volume to extend, type C:

9) In Size to expand the volume (MB) : Type the size you would like to increase.  In my example, the additional space I like to increase is 1GB (1024 MB)
Enter a brief description of your file (required)10) Refresh or Rescan disks, to see the new space.  It might take some time for the disk to expand depends on the disk size you increased
Enter a brief description of your file (required)Tips:  

1) If your Windows 2003 VM is a domain controller, you might get the error “Unable to connect to C: or it does not exist” during extpart. Please try stopping the "Indexing Services" or "File Replication Services" and then run the the extpart.

2) This tutorial is written especially for Windows 2003 VMs and use ExtPart tool. If you need to increase or resize VMDK for other opeartion systems (Windows 2008, R2, 7...etc) or using other tools. Please also read this excellent article written by VMware Expert Hanccoka. HOW TO:  Resize a VMware (VMDK) Virtual Disk

I hope this tutorial is helpful!

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