diff --git a/apps/server/src/cli/uninstall.test.ts b/apps/server/src/cli/uninstall.test.ts
index 1e81e8b8c7a9a..d2ad673408d40 100644
--- a/apps/server/src/cli/uninstall.test.ts
+++ b/apps/server/src/cli/uninstall.test.ts
@@ -5,7 +5,7 @@ import * as FileSystem from "effect/FileSystem";
 import * as Path from "effect/Path";
 import * as HostProcess from "@t3tools/shared/HostProcess";
 
-import { findOwnedLauncher } from "./uninstall.ts";
+import { findOwnedLauncher, spawnWindowsRemoval } from "./uninstall.ts";
 
 it.layer(NodeServices.layer)("t3 uninstall launcher", (it) => {
   it.effect("claims only a launcher that points into this home's runtime tree", () =>
@@ -35,3 +35,26 @@ it.layer(NodeServices.layer)("t3 uninstall launcher", (it) => {
     }).pipe(Effect.scoped, Effect.provideService(HostProcess.Platform, "linux")),
   );
 });
+
+it.live.runIf(HostProcess.Platform.defaultValue() === "win32")(
+  "t3 uninstall has cmd.exe remove the runtime directory, preserving spaces and literal environment-variable syntax",
+  () =>
+    Effect.gen(function* () {
+      const fs = yield* FileSystem.FileSystem;
+      const path = yield* Path.Path;
+      const root = yield* fs.makeTempDirectoryScoped({ prefix: "t3-uninstall-" });
+      const runtimeDir = path.join(root, "t3 home %COMSPEC% !COMSPEC! & data", "runtime");
+      yield* fs.makeDirectory(path.join(runtimeDir, "versions", "1.0.0"), { recursive: true });
+      yield* fs.writeFileString(path.join(runtimeDir, "versions", "1.0.0", "t3.exe"), "");
+
+      const child = spawnWindowsRemoval(process.env.ComSpec ?? "cmd.exe", runtimeDir);
+      yield* Effect.callback<void, Error>((resume) => {
+        child.once("error", (error) => resume(Effect.fail(error)));
+        child.once("exit", (code) =>
+          resume(code === 0 ? Effect.void : Effect.die(`cmd.exe exited with ${code}`)),
+        );
+      });
+
+      assert.isFalse(yield* fs.exists(runtimeDir));
+    }).pipe(Effect.scoped, Effect.provide(NodeServices.layer)),
+);
diff --git a/apps/server/src/cli/uninstall.ts b/apps/server/src/cli/uninstall.ts
index 830c0cc543271..33aa63fe4798e 100644
--- a/apps/server/src/cli/uninstall.ts
+++ b/apps/server/src/cli/uninstall.ts
@@ -61,6 +61,27 @@ export const findOwnedLauncher = Effect.fn("cli.uninstall.find_launcher")(functi
   return launcherOwnsVersionsDir(path, input.versionsDir, resolved) ? input.launchedAs : undefined;
 });
 
+// cmd.exe needs verbatim quoting and a literal path, with delayed expansion disabled.
+export function spawnWindowsRemoval(comspec: string, dir: string) {
+  return NodeChildProcess.spawn(
+    comspec,
+    [
+      "/d",
+      "/v:off",
+      "/s",
+      "/c",
+      '"ping -n 3 127.0.0.1 >nul & rmdir /s /q "%T3_UNINSTALL_RUNTIME%""',
+    ],
+    {
+      env: { ...process.env, T3_UNINSTALL_RUNTIME: dir },
+      windowsVerbatimArguments: true,
+      detached: true,
+      stdio: "ignore",
+      windowsHide: true,
+    },
+  );
+}
+
 const planUninstall = Effect.fn("cli.uninstall.plan")(function* (input: {
   readonly baseDir: string;
 }) {
@@ -176,14 +197,7 @@ const runUninstall = Effect.fn("cli.uninstall.run")(function* (input: {
       const runtimeDir = plan.runtimeDir;
       const comspec = environment["ComSpec"] ?? environment["COMSPEC"] ?? "cmd.exe";
       yield* Effect.try({
-        try: () => {
-          const child = NodeChildProcess.spawn(
-            comspec,
-            ["/d", "/c", `ping -n 3 127.0.0.1 >nul & rmdir /s /q "${runtimeDir}"`],
-            { detached: true, stdio: "ignore", windowsHide: true },
-          );
-          child.unref();
-        },
+        try: () => spawnWindowsRemoval(comspec, runtimeDir).unref(),
         catch: () =>
           new CliUninstallError({
             reason: `Could not schedule removal of ${runtimeDir}. Delete it yourself once this window is closed.`,