diff --git a/packages/util/native-command/README.i18n.yaml b/packages/util/native-command/README.i18n.yaml
index 0313a056c5..0f50bd4a58 100644
--- a/packages/util/native-command/README.i18n.yaml
+++ b/packages/util/native-command/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/util/native-command/README.md
-README.md: 5009792353f913df57fb90b352d52e7f7715a0d6
-README.zh.md: b214f5996d4f5a4b79cd9a698d09d7737815fd42
+README.md: 7d3aa8b8f35d483f9936440cb4cd35bf1e785f1a
+README.zh.md: 672bbd6eba39ab88f1822562e7fc6a780d3c276e
diff --git a/packages/util/native-command/README.md b/packages/util/native-command/README.md
index 5009792353..7d3aa8b8f3 100644
--- a/packages/util/native-command/README.md
+++ b/packages/util/native-command/README.md
@@ -109,6 +109,7 @@ Linux association discovery and explicit launching require GIO. Missing native c
 These limits define when this runner is not the right tool. They are current package constraints, not a task backlog.
 
 - Command output uses Node’s `execFile` buffer limit; oversized replies reject. Use the subprocess capability for streaming output.
+- A Windows handler icon appears only when the Shell resolves its indirect reference; an unresolved reference falls back to the handler executable, and a handler that names none — a packaged handler may report an AUMID or family name — yields no icon.
 - A Windows host needs an interactive desktop session. In a non-interactive session — a service, or a scheduled task without an interactive logon — `explorer.exe` invokes no file association and still exits 1 after about a second (an SSH session 0 on Windows 11 ARM64 build 26200), so an open reports success having opened nothing; a caller's abort signal turns that wait into a timeout rather than a hang. An `Invoke-Item` command resolves the association in-process there, and its directory failure arrives as a non-zero exit code. No fallback for that session is implemented.
 
 <a id="dev-note"></a>
diff --git a/packages/util/native-command/README.zh.md b/packages/util/native-command/README.zh.md
index b214f5996d..672bbd6eba 100644
--- a/packages/util/native-command/README.zh.md
+++ b/packages/util/native-command/README.zh.md
@@ -109,6 +109,7 @@ Linux 的关联查询和指定应用启动需要 GIO。缺少原生命令时查
 这些限制说明本运行器何时不是合适的工具。它们是当前包约束，不是任务积压。
 
 - 命令输出受 Node 的 `execFile` 缓冲上限约束，超过上限时拒绝结果。流式输出由 subprocess 能力处理。
+- Windows 关联处理器的图标只在 Shell 能解析其间接引用时显示；解析失败时回退到处理器的可执行文件，处理器没有给出可执行文件（打包处理器可能只报 AUMID 或家族名）时则没有图标。
 - Windows 主机需要交互桌面会话。在非交互会话（服务，或没有交互登录的计划任务）中，`explorer.exe` 不调用任何文件关联，且仍在约 1 秒后以退出码 1 返回（Windows 11 ARM64 build 26200 的 SSH session 0 实测），于是「打开」会报告成功却什么都没打开；调用方的 abort 信号把这段等待变成超时而不是挂死。同一目标改用 `Invoke-Item` 命令时可在该会话内解析关联，目录失败也会以非零退出码报出。该会话下的兜底尚未实现。
 
 <a id="dev-note"></a>
diff --git a/packages/util/native-command/src/file-applications-windows.ts b/packages/util/native-command/src/file-applications-windows.ts
index c9950875cd..6995ec0b8d 100644
--- a/packages/util/native-command/src/file-applications-windows.ts
+++ b/packages/util/native-command/src/file-applications-windows.ts
@@ -1,4 +1,7 @@
 /** Windows Shell association queries and invocation; paths are encoded data, never PowerShell expressions. */
+import { mkdtemp, rm, writeFile } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
 import type { NativeCommandRunner } from './runner.ts'
 
 /** Shell interfaces are declared in their native vtable order; Invoke preserves packaged-app and DDE handling. */
@@ -155,10 +158,12 @@ public static class DshFileAssociations {
       if (small != IntPtr.Zero) DestroyIcon(small);
     }
   }
-  static string IconData(IHandler handler) {
+  // Best-effort fallback: some handlers return their executable path from GetName, but a
+  // packaged handler's name may be an AUMID or family name, which extracts no icon.
+  static string IconData(IHandler handler, string id) {
     string source = null; int index = 0;
     try { handler.GetIconLocation(out source, out index); } catch (Exception) {
-      // A handler without a drawable icon location falls back to its executable.
+      // A handler without a drawable icon location falls back to its name.
     }
     if (!String.IsNullOrEmpty(source)) {
       source = Environment.ExpandEnvironmentVariables(source);
@@ -169,14 +174,9 @@ public static class DshFileAssociations {
       var icon = PngFromIconSource(source, index);
       if (icon != null) return icon;
     }
-    // Packaged handlers name the executable only in GetName; extract there too.
-    string executable = null;
-    try { handler.GetName(out executable); } catch (Exception) {
-      // A handler that names no executable has no icon to fall back to.
-    }
-    return String.IsNullOrEmpty(executable) || String.Equals(executable, source, StringComparison.OrdinalIgnoreCase)
+    return String.IsNullOrEmpty(id) || String.Equals(id, source, StringComparison.OrdinalIgnoreCase)
       ? null
-      : PngFromIconSource(executable, 0);
+      : PngFromIconSource(id, 0);
   }
   static void Visit(string path, Action<IHandler> visit) {
     var extension = Path.GetExtension(path);
@@ -203,7 +203,7 @@ public static class DshFileAssociations {
       string id, name;
       handler.GetName(out id); handler.GetUIName(out name);
       if (!seen.Add(id)) return;
-      apps.Add(new Application { id = id, name = name, icon = IconData(handler),
+      apps.Add(new Application { id = id, name = name, icon = IconData(handler, id),
         @default = String.Equals(id, executable, StringComparison.OrdinalIgnoreCase) || String.Equals(id, appId, StringComparison.OrdinalIgnoreCase) });
     });
     return apps.ToArray();
@@ -236,7 +236,8 @@ public static class DshFileAssociations {
 }`
 
 /**
- * Execute the Windows Shell adapter in a Unicode STA PowerShell process.
+ * Execute the Windows Shell adapter in a Unicode STA PowerShell process; the adapter
+ * source is a private temporary script file, removed once the call settles.
  * @param path - Windows file path, translated by the caller for WSL.
  * @param application - registered handler to invoke; null requests the application list.
  * @param signal - caller cancellation.
@@ -257,8 +258,19 @@ $path = [Text.Encoding]::UTF8.GetString([Convert]::FromBase64String('${encodedPa
 $application = [Text.Encoding]::UTF8.GetString([Convert]::FromBase64String('${encodedApplication}'))
 ${application === null ? 'ConvertTo-Json -InputObject @([DshFileAssociations]::List($path)) -Depth 4 -Compress' : '[DshFileAssociations]::Open($path, $application)'}
 `
-  const result = await run('powershell.exe', [
-    '-NoProfile', '-NonInteractive', '-STA', '-EncodedCommand', Buffer.from(script, 'utf16le').toString('base64'),
-  ], signal)
-  return result.stdout
+  // The script travels as a file, not as command-line data: -EncodedCommand grew with the
+  // embedded C# and overflowed the 32767-character CreateProcess limit for long paths.
+  // PowerShell 5.1 decodes a -File script as ANSI unless it carries a BOM; the BOM keeps
+  // the embedded UTF-8 source intact.
+  const directory = await mkdtemp(join(tmpdir(), 'dsh-native-command-'))
+  const scriptPath = join(directory, 'associations.ps1')
+  try {
+    await writeFile(scriptPath, `\uFEFF${script}`, 'utf8')
+    const result = await run('powershell.exe', [
+      '-NoProfile', '-NonInteractive', '-STA', '-ExecutionPolicy', 'Bypass', '-File', scriptPath,
+    ], signal)
+    return result.stdout
+  } finally {
+    await rm(directory, { recursive: true, force: true })
+  }
 }
diff --git a/packages/util/native-command/tests/file-applications.spec.ts b/packages/util/native-command/tests/file-applications.spec.ts
index 37538b239c..658a44f32c 100644
--- a/packages/util/native-command/tests/file-applications.spec.ts
+++ b/packages/util/native-command/tests/file-applications.spec.ts
@@ -1,4 +1,5 @@
 /** File association results and explicit handler authorization at the native command adapter. */
+import { readFile } from 'node:fs/promises'
 import { describe, expect, it, vi, onTestFinished } from 'vitest'
 import * as runner from '../src/runner.ts'
 import { nativeFileApplications, openNativeFileApplication } from '../src/file-applications.ts'
@@ -118,16 +119,45 @@ it('uses the production command adapter and current platform when no override is
 
 
 it('encodes Windows query and invocation data separately from native adapter source', async () => {
-  const run = vi.fn<runner.NativeCommandRunner>(async () => ({ stdout: JSON.stringify([application]), stderr: '' }))
+  const scripts: string[] = []
+  const run = vi.fn<runner.NativeCommandRunner>(async (_command, args) => {
+    scripts.push(await readFile(args.at(-1)!, 'utf8'))
+    return { stdout: JSON.stringify([application]), stderr: '' }
+  })
   const path = "C:\\测试\\a'; write-host nope.mp3"
   expect(await nativeFileApplications(path, signal, { platform: 'win32', run })).toEqual([application])
-  const query = Buffer.from(run.mock.calls[0]![1].at(-1)!, 'base64').toString('utf16le')
-  expect(query).toContain(Buffer.from(path).toString('base64'))
-  expect(query).not.toContain(path)
-  expect(query).toContain('::List($path)')
+  expect(scripts[0]!).toContain(Buffer.from(path).toString('base64'))
+  expect(scripts[0]!).not.toContain(path)
+  expect(scripts[0]!).toContain('::List($path)')
   await openNativeFileApplication(path, application.id, signal, { platform: 'win32', run })
-  expect(Buffer.from(run.mock.calls[1]![1].at(-1)!, 'base64').toString('utf16le')).toContain('::Open($path, $application)')
+  expect(scripts[1]!).toContain('::Open($path, $application)')
   expect(run.mock.calls[1]![0]).toBe('powershell.exe')
+  expect(run.mock.calls[1]![1]).toEqual(['-NoProfile', '-NonInteractive', '-STA', '-ExecutionPolicy', 'Bypass', '-File', expect.any(String)])
+  // PowerShell 5.1 reads a -File script as ANSI without the BOM.
+  expect(scripts[1]!).toMatch(/^\uFEFF/)
+})
+
+it('keeps the complete Windows command line below the CreateProcess limit for long multibyte paths', async () => {
+  const run = vi.fn<runner.NativeCommandRunner>(async () => ({ stdout: '[]', stderr: '' }))
+  const paths = [
+    // 222 characters; this path measured 32883 characters of command line while the script travelled there.
+    `C:\\work\\${'测'.repeat(210)}.txt`,
+    `C:\\work\\${'测'.repeat(3000)}.txt`,
+  ]
+  for (const path of paths) await nativeFileApplications(path, signal, { platform: 'win32', run })
+  const commandLines = run.mock.calls.map(call => [call[0], ...call[1]].join(' '))
+  expect(commandLines).toHaveLength(paths.length)
+  commandLines.forEach((line, index) => {
+    const path = paths[index]!
+    // Windows CreateProcess rejects a command line over 32767 characters; the script and
+    // the encoded path are no longer part of the line, so it stays near 100 characters.
+    expect(line.length).toBeLessThan(1_000)
+    expect(line).toContain('powershell.exe')
+    expect(line).toContain('-File')
+    // The path travels as encoded data inside the script file, never on the command line.
+    expect(line).not.toContain(path)
+    expect(line).not.toContain(Buffer.from(path).toString('base64'))
+  })
 })
 
 it('uses the Windows desktop for WSL paths and rejects an empty translation', async () => {