Virtual Disk Manager

When trying to shrink a partition in Win7 x64 the following alert is given:

Virtual Disk Manager: The service cannot be started, either because it is disabled or because it has no enabled devices associated with it.

How can I enable the service, and also it cannot be found in services.msc

Update: >_< The issue was the disk defragmenter service was disabled as I have an SSD however the virtual drive manager is tied to the service. Disabling disk defragementer will disable virtual drive manager which is required for partition shrinking.

That and two hours of fiddling yielded no solution but a single post to sevenforums resulted in an epiphany that revealed the answer

Had this same problem when trying to shrink some volumes in disk management, couldn't figure out why. Turned disk defragmenter back on temporarily and that did it.

Something it seems no one mentions as a possible side effect when turning off disk defragmenter on an SSD. At least of all the writeups I've seen on it. Should probably be mentioned.

Thanks, was about to freak out.

That is strange Aaron. I don't see how Disk Defragmenter is related to the Virtual Disk service being disabled.

Did you turn off only the Disk Defragmenter Schedule for the SSD? I have the schedule turned off completely, and do not have any problems using Disk Management to shrink a partition.


Here's what I have for the Virtual Disk service and it's dependencies.

My Virtual Disk service wasn't disabled or missing with Disk defragmenter service disabled (and defrag tasks disabled). It was like yours there - Started/manual, but it would throw that error up that the OP had as well, trying to shrink any volume. Even stopped and restarted it a few times without success.

Virtual Disk Manager: The service cannot be started, either because it is disabled or because it has no enabled devices associated with it.

I found this thread, and enabled and started the defrag service, and worked right away. Must be related to it in someway.

Yep, that's what it is. I only had the Disk Defragmenter schedule turned off so that Disk Defrafmenter would not run automatically. When I disabled the Disk Defragmenter service, I got the same error.

I'll add a warning to all of the partition tutorials now about this.

As you did Brink, I found that there are no dependencies linking Disk defrag to volume shrinking with virtual disk service, according to technical documents, however I have found as in my first post that it is not possible to shrink a partition without disk defrag service enabled.

My understanding after some research is that the issue is not related to service dependencies but rather hinges on the manner in which the virtual disk service relies on the disk defragmenter service to reallocate space reserved for meta data/virtual page file. While there could be no data in the end of the partition the last block is always reserved for meta data that for some reason can only be placed at the end of the drive and this section can only be moved by the built in ms defrag tool.

I have used numerous third party defrag programs to pack all the data into the front of a drive both SSD and HDD and the result was the same, without the disk defrag service enabled the partition cannot be shrunk.

As for partition expansion that was not something I tested but may do so just to see what the result is.

Edit: This issue is only relevant to shrinking a partition, and has no bearing on extending a partition.

Thanks for this everyone. Saved me hours of error hunting :)
Ciao.