Claude Desktop quietly runs a 2 GB VM on every launch — here's the setting that turns it off

A GitHub issue open since February hit Hacker News' front page on June 10, 2026: Claude Desktop spawns a ~1.8 GB Hyper-V VM (Vmmem) on Windows — and a similar VM on macOS — every time it starts, even for chat-only use. The VM powers the Cowork sandbox. A community-reported config flag, secureVmFeaturesEnabled: false, appears to disable it.

If Claude Desktop feels heavier than a chat app should, it is not your imagination. The app boots a full virtual machine on every launch — about 1.8 GB of RAM on Windows (visible as Vmmem in Task Manager) and 1.9–3+ GB on macOS via Apple’s Virtualization framework — even if all you ever do is chat. The bug report has been open since February 26, 2026 and hit Hacker News’ front page on June 10 with 400+ points. (Source: GitHub issue #29045)

Key facts:

On Windows, Claude Desktop triggers the Hyper-V Host Compute Service at launch and spawns a VM consuming ~1,800 MB, before you type anything. (Source: GitHub issue #29045, 2026-02-26)
macOS is affected too: users report 1.89 GB on an M4 MacBook Air and 3 GB+ on M4 Pro machines; one Hacker News commenter measured 12 GB. (Source: GitHub issue comments; Hacker News, 2026-06-10)
The VM exists to sandbox Cowork, Claude’s local agent mode. Community analysis says Anthropic pre-boots it at startup to make Cowork launch faster — whether you use Cowork or not. (Source: GitHub issue comments)
It costs disk as well as RAM: a ~2 GB rootfs.vhdx download on Windows and a VM bundle users measure at 6–10 GB on macOS, with no built-in way to remove it. (Source: GitHub issue comments; Hacker News, 2026-06-10)
One user found 2,689 stale Cowork session files that were never cleaned up. (Source: GitHub issue #29045)
As of June 11, the issue is still open with no public response from Anthropic in the thread.

Windows Task Manager showing Vmmem consuming about 1.8 GB of RAM with Claude Desktop running Vmmem at ~1.8 GB right after launching Claude Desktop, before any Cowork use. (Source: GitHub issue #29045, reported by davidellett)

The fix: one config flag

On June 10, a commenter on the issue posted what looks like the cleanest workaround so far. In Claude Desktop, open Developer → Open App Config File and add:

{
  "preferences": {
    "secureVmFeaturesEnabled": false
  }
}

Restart the app and the VM should no longer spawn. (Source: GitHub issue comment by gtirloni, 2026-06-10 — community-reported; we have not independently verified it, and it presumably disables Cowork.)

If the flag doesn’t work for you

Windows, nuclear option: Disable-WindowsOptionalFeature -Online -FeatureName "VirtualMachinePlatform" -NoRestart in an admin PowerShell. This blocks the VM entirely but also breaks Cowork — and anything else on your machine that needs the platform, like WSL2. (Source: GitHub issue #29045)
Kill the processes: Stop-Process -Name vmwp -Force reclaims the RAM and chat keeps working, though some users report the VM respawns on its own. (Source: GitHub issue comments)
macOS: fully quitting Claude Desktop (Cmd+Q) releases the VM memory — until the next launch.

The bigger picture: if you mostly use Claude for coding work anyway, the desktop app’s overhead is a good reason to live in the terminal instead. Claude Code as a daily driver covers that setup, and if you are switching models too, see how to switch to Claude Fable 5.