Extending a VM Windows C drive partition using Dell EXTPart

I get many requests to extend the C:\ (or any other drive) 

Most times these are for VMs – so it is pretty easy right? Extend the amount of disk allocated to the virtual machine, then extend in Computer Management – or using diskpart?

Well this does not always work – see, Windows does not really like you messing with system drive.
Dell have come up with a brilliant tool called EXTPart

http://support.dell.com/support/downloads/download.aspx?c=us&cs=19&l=en&s=dhs&releaseid=R64398&formatcnt=2&fileid=83929 

All you need to do now is provision the extra space to the VM, then run the tool at the command line and follow the wizard:

C:\>extpart.exe
ExtPart - Utility to extend basic disks (Build 1.0.4)
(c) Dell Computer Corporation 2003

Volume to extend (drive letter or mount point): c:
Current volume size : 66285 MB (69504860160 bytes)
Current partition size : 76285 MB (79990815744 bytes)
Size to expand the volume (MB): 76285

 That’s it – job done . . zero downtime  

 Note: This works differently if you have a clustered disk to extend.