Expanding a Parallels Disk Image…What They Don’t Tell You

author: tom

On the initial install of Windows XP under Parallels, I was very conservative in the disk space I allocated to it. After Windows repeatedly yelling at me to do something about the lack of disk space I figured I would.

When setting up the Windows Virtual Machine, I had the image set to “Expanding.” A bit deceiving…for there is a procedure that is not “included” in the help file for accomplishing this:

Find your hard disk image file on the host machine (in this case Mac OS).. Run the Parallels ImageTool on it and expand it to the desired amount.
Duplicate the hard disk image you wish to expand on the host machine.
Open Parallels then the preferences for the virtual machine you are using. Change the hard disk image path the duplicate image.
Add a new hard disk via the add button and add a new hard disk. Set the path to the original image…the purpose of this and the above step is to boot from the duplicate disk so that Windows can have full access to the disk (original image) you wish to expand.
Boot up Windows. Then navigate to Start->Run. Enter “DISKPART” and press Run/Enter.
In the new window that appears type: “list volume”
After that process runs, a list of disks appears. Notice that Volume 1 and Volume 2 look identical. *Note: Volume 2 should be the original hard disk image.
Select Volume 2 by typing: “select volume 2″ then extend it by typing “extend” once that is complete type “exit” and shut down Windows.
Clean up the Virtual Machine preferences by deleting the second hard disk and switching the hard disk 1 path back to the original hard disk image.
Restart Windows. Rebooting may be necessary if Windows “detects new hardware.”

This procedure allows Windows to see the extra space that Parallels has allocated. One day maybe Windows will be easier to use……if hell freezes over.

Tags: ImageTool. Disk Image, Mac, Parallels
Posted in Apple | View blog reactions

22 Responses

date: March 6th, 2007

Perfect! Exactly what I was looking for. I appreciate the help.

spoken by: Jeff Douglas

date: June 19th, 2007

work a treat. quite simple in the end. thanks so much.

spoken by: matt

date: June 19th, 2007

works a treat. quite simple in the end. thanks so much.
(forgot an ’s’ and the website in my previous post)

spoken by: matt

date: October 25th, 2007

thank you, thank you, thank you!

spoken by: mdp

date: December 14th, 2007

Freekin AWESOME! Thanks dude. Great tutorial! Works like a champ!

spoken by: Ian

date: December 23rd, 2007

Sweet solution, as a new Mac user I really appreciate the line by line instruction. Thank for posting this solution.

spoken by: John M Smith

date: March 5th, 2008

Excellent! This worked like a charm, and is much simpler than the other procedures posted, including those posted by Parallels. Thank you!

spoken by: Roger S. Cohen

date: April 23rd, 2008

Wonderful, wonderful. Thanks for solving this for me!

spoken by: Greg

date: August 1st, 2008

Awesome. I was about to reload the OS. Thanks for the solution.

spoken by: Tim Timalsina

date: September 5th, 2008

Amazing! Thanks a lot!

spoken by: DazFTM

date: October 9th, 2008

What do you mean by “duplicate the hard disk image you wish to expand on the host machine”? And how do I go about doing that?

spoken by: Austin

date: October 22nd, 2008

@austin “duplicate the hard disk image you wish to expand on the host machine” means copy the existing virtual machine and paste a duplicate. You will need a duplicate image later in the process.

spoken by: tom

date: December 19th, 2008

I have been all over the internet trying to find a solution that worked. Yours is the most complete set of instructions I found, and the only one that worked. Thank you so much!

spoken by: Dede

date: December 30th, 2008

Go on with your bad self!!! It works like a charm. Yes!!!! Many thanks sir!!

spoken by: Henry

date: January 30th, 2009

“Towering genius disdains the beaten path. It seeks regions hitherto unexplored.”…. A Lincoln

spoken by: Matteo

date: February 1st, 2009

Another satisfied customer. Thanks for putting this up. I’m a Mac guy so it would have taken me approximately 2.4 years to figure this out for myself.

spoken by: tom

date: February 2nd, 2009

Almost worked a treat.

Removing the hard disk copy it did default over to the original hard disk but then wouldn’t boot.

Removing the original and adding it back seemed to fix something and it started as it intended.

spoken by: James Jones

date: March 30th, 2009

Fantastically simple. Thanks so much for posting this!!

spoken by: Jon

date: April 15th, 2009

Worked!!! After a few weeks trying what the manual suggested without results, this was a life saver.
I do have to say the instructions are not as clear as they could be as not all the correct steps are listed properly, so there was a bit of guess work. In the end all worked just fine – Thanks!
Now is there a way to make Parallels for Windows hard disk size any bigger?

Thanks and God Bless!

spoken by: Bill

date: May 27th, 2009

Even after reading all the positive responses, I was amazed when this worked! I am using Vista Business. For some reason I had to switch back to the windows copy disk but when I did this and repeated steps 5-8 it worked and I had exactly what I wanted. I didn’t bother with step #9 since this is where the problem occurred the first time. Even though I can still see the original volume/hard disk (the windows virtual disk) it doesn’t seem to actually be taking up any space on the actual hard drive. I am amazed, I didn’t really think this would work… Thanks for the help. Looking forward to the day when I don’t need windows at all, unfortunately, I still rely on it for a few applications and work specific web sites that just won’t work right with the Mac. Thanks again! Don’t be afraid to try this fix.

spoken by: RJD

date: July 1st, 2009

On ‘DISKPART’, I type ‘extend’ and it say’s something about NTFS and does not let me extend. Could somebody help? Appreciate the instructions by the way.

Thanks, Jamie.

spoken by: Jamie

date: October 7th, 2009

Your instructions were impeccable and worked very nicely!

Thank You!!

spoken by: Herb Jones

Dec 1 2006