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How I resized a Windows partition – Parallels Support Forum

I successfully resized my Windows 2003 installation today using the following process.

1. Copy the HDD drive image file and rename
2. Use Image Tools to resize the original HDD file
3. Change your VM profile to boot off of the copied HDD image and add the original, resized image as a second hard disk
4. Once booted, open CMD prompt and run DISKPART
5. View volumes in DISKPART with the command list volume. Note which volume is your original, resized partition
6. Select that partition using the DISKPART command select volume # where # is the partition number.
7. Enter the command extend
8. Enter the command exit
9. Exit Windows and change the VM profile to once again boot from the original, resized image file. You can disconnect (and delete?) the copied image file from the VM profile.

I don’t know if DISKPART can be used on Windows XP, etc. but I know that you can download it from Microsoft. Google diskpart windows download.

As mentioned, this worked for me though I cannot guarantee that this will work in all situations.

Cool. Widely reported to work, no need to figure shit out by myself later.