diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7295e24d339..1d01248f7b4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -80,6 +80,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- UI/Windows: quote resolved pnpm `.cmd` launcher paths before spawning UI install/build/test commands so Node installs under `C:\Program Files` no longer fail as `C:\Program`. Fixes #45275. Thanks @Kobevictor, @stoppieboy, and @iubns.
 - Plugins/uninstall: remove tracked plugin files from their recorded managed extensions root even when the current state directory points somewhere else, so `openclaw plugins uninstall --force` does not leave the plugin discoverable. Thanks @shakkernerd.
 - Agents/runtime: add `agentRuntime.id` as the canonical config key, migrate
   legacy runtime-policy configs with `openclaw doctor --fix`, and route
diff --git a/scripts/ui.js b/scripts/ui.js
index 8f7b8e0cf02..0b5f4be436e 100644
--- a/scripts/ui.js
+++ b/scripts/ui.js
@@ -76,6 +76,10 @@ export function assertSafeWindowsShellArgs(args, platform = process.platform) {
   );
 }
 
+export function prepareSpawnCommand(cmd, platform = process.platform) {
+  return shouldUseShellForCommand(cmd, platform) ? `"${cmd}"` : cmd;
+}
+
 function createSpawnOptions(cmd, args, envOverride) {
   const useShell = shouldUseShellForCommand(cmd);
   if (useShell) {
@@ -92,7 +96,7 @@ function createSpawnOptions(cmd, args, envOverride) {
 function run(cmd, args) {
   let child;
   try {
-    child = spawn(cmd, args, createSpawnOptions(cmd, args));
+    child = spawn(prepareSpawnCommand(cmd), args, createSpawnOptions(cmd, args));
   } catch (err) {
     console.error(`Failed to launch ${cmd}:`, err);
     process.exit(1);
@@ -113,7 +117,7 @@ function run(cmd, args) {
 function runSync(cmd, args, envOverride) {
   let result;
   try {
-    result = spawnSync(cmd, args, createSpawnOptions(cmd, args, envOverride));
+    result = spawnSync(prepareSpawnCommand(cmd), args, createSpawnOptions(cmd, args, envOverride));
   } catch (err) {
     console.error(`Failed to launch ${cmd}:`, err);
     process.exit(1);
diff --git a/test/scripts/ui.test.ts b/test/scripts/ui.test.ts
index 170d964f369..86c1ca66243 100644
--- a/test/scripts/ui.test.ts
+++ b/test/scripts/ui.test.ts
@@ -1,5 +1,9 @@
 import { describe, expect, it } from "vitest";
-import { assertSafeWindowsShellArgs, shouldUseShellForCommand } from "../../scripts/ui.js";
+import {
+  assertSafeWindowsShellArgs,
+  prepareSpawnCommand,
+  shouldUseShellForCommand,
+} from "../../scripts/ui.js";
 
 describe("scripts/ui windows spawn behavior", () => {
   it("enables shell for Windows command launchers that require cmd.exe", () => {
@@ -14,6 +18,16 @@ describe("scripts/ui windows spawn behavior", () => {
     expect(shouldUseShellForCommand("/usr/local/bin/pnpm", "linux")).toBe(false);
   });
 
+  it("quotes Windows shell launcher paths before passing them to spawn", () => {
+    expect(prepareSpawnCommand("C:\\Program Files\\nodejs\\pnpm.cmd", "win32")).toBe(
+      '"C:\\Program Files\\nodejs\\pnpm.cmd"',
+    );
+    expect(prepareSpawnCommand("C:\\Program Files\\nodejs\\pnpm.exe", "win32")).toBe(
+      "C:\\Program Files\\nodejs\\pnpm.exe",
+    );
+    expect(prepareSpawnCommand("/usr/local/bin/pnpm", "linux")).toBe("/usr/local/bin/pnpm");
+  });
+
   it("allows safe forwarded args when shell mode is required on Windows", () => {
     expect(() =>
       assertSafeWindowsShellArgs(["run", "build", "--filter", "@openclaw/ui"], "win32"),