Windows 10 Parallels disk image is far larger than space used by OS

[koppah]

My Windows 10 disk image is 271GB on disk, but is only using 32GB if I boot it up and check in Windows. Is this a known issue? Reclaim space doesn't do anything.

 

[Axel_Luttgens]

Hello koppah,
This seems to be a general problem with PD 16 and any guest OS.
See for example

https://forum.parallels.com/threads/pd16-trim-for-guest-is-not-working.350900/​

Disk space reclaiming doesn't seem to be effective anymore, and the guest's VM space tend to irremediably grow forever.
This tend to make PD quite unusable...
Axel