Quick answer: Virtual machine disk files can be huge. Move or compact them through the VM software instead of deleting disk files blindly.
Why this uses C drive space
VMs store virtual disks, snapshots, ISO files, and checkpoints. These files can consume tens or hundreds of gigabytes.
Safe cleanup steps
- Open the VM manager you use.
- Check each VM's disk and snapshot size.
- Delete old snapshots from inside the VM tool.
- Move VM storage to a larger drive if supported.
- Compact virtual disks after cleanup inside the guest OS.
What to avoid
Do not delete VHD, VHDX, VDI, or VMDK files unless you are sure the VM is no longer needed.
How DiskTidy helps
DiskTidy can help you review temporary files, browser cache, cleanup candidates, and large files before deleting anything. It is designed for local, review-first cleanup instead of blind one-click deletion.