Today I was working on expanding a disk on my Exchange servers. The task is pretty simple, you open the virtual machine settings, select the disk you want to expand, expand it and then log in to windows, open disk management MMC, rescan disks and extend the partition.

Once I extended the partition, I got the following error “The Parameter Is Incorrect” and even though in disk management the partition is extended, in Windows, we don’t see the drive changes, meaning the drive remained the same size. The problem is that even through the partition was extended, the file system was not. Here’s the KB article explaining this.

To fix you can run diskpart and extend the file system.

1. Open command prompt

2. type “diskpart”

3. Type “select volume #” (Where the number is the number of the volume you’re extending)

4. Type “Extend Filesystem”

The file system should now be extended and it should be reflected when you open My Computer.