Resize virtual machine's system volume

I have performed this action several times with windows server 2003 guests in our environment. Remove the drive, add it to another guest, expand the space in vc or by running vmkfstools, login and extend using diskpart.  Occassionally, diskpart will throw an error and not expand the disk (new space is visible in disk manager).  The only way I was able to resolve it was to attach it to a windows 2000 guest and run diskpart from there.  Anyone know why this would work sometimes and not others?
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leegclystvaleConnect With a Mentor Commented:

As per usacadena's post above, I have just successfully completed a resize of W2k3 C: partition from 10gb to 40gb. The steps are like this:
Pre-requirements I used
>Same OS and Service pack number (w2k3 R2 in my case)
>ESXi host server
>Downloaded EXTPART.exe from and copied to the c:\ of VM I am going to do the work on (I'll refer to it as VM-B)

The steps are to add the c:\ partition of VM-A to another VM (VM-B) as a secondary disk drive, then boot VM-B into Windows, go into Disk management, and run EXTPART to increase the system, partition size

a) Shutdown VM that you want to resize system c:\ partition on (VM-A)
b) Shutdown VM that you want to do the work on (VM-B)
c) On VM-A select "Edit settings"
d)On VM-A select "Hard Disk 1" and on capacity input your required size (eg. 10gb to 40gb in my case)
e)On VM-B go to "Edit settings" chose "Add" and the "Hard disk".
f) Browse the datastore to find the VMDK file for VM-A
g) Follow wizard Next next next bla bla bla!
h) Starty VM-B, log in (i used domain admin account)
i) Go to My Computer>Manage>Disk Management. You will see the unallocated space (i had basic disks) MAke a note of drive letter of the 2nd hard disk as you want to extend this. (e: in my case)
j) Go to command prompt and type c:\EXTPART E: 30720 (The command is extending the E: drive by the amount of 30gb. It already knows about the 10gb so your command is just the increased amount)
k)It will state a success or not
l) Reboot VM-B and then go to "Edit settings" and remove 2 disk drive.
J) Fire up VM-A and it is done.
It maybe a diskpart version issue.
Can't find the exact article.

See this link to stsrt:

Error codes for diskpart:
Paul SolovyovskySenior IT AdvisorCommented:
You can also use vConverter to point to source and destination and schedule the conversion.  During the conversion (V2V) you can set it up for resize.  This makes the process automated.  

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1) Shutdown the VM or target, whose C drive you want to extend
2) Select "Edit Settings"
3) Select "Hard Disk 1" and on Capacity section increase the "New Size" from 6 to 20 GB
4) Using another VM host  that has Windows 2003 Server OS, attach  targetname.vmdk as another hard drive
5) Reboot  this host
6) Restart thehosy VM t
7) Open CMD prompt type "extpart c: 20480"8) Remove T drive
9) Reattach the drive to orginal target VM

ExtrPart from dell website: 
roostercogburnAuthor Commented:
Thanks for not giving any points.  I will not answer any more of you questions going forward "roostercogburn"
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