diff --git a/packages/ui/src/components/sections/openchamber/OpenCodeCliSettings.tsx b/packages/ui/src/components/sections/openchamber/OpenCodeCliSettings.tsx
index 110585e1..5a66daba 100644
--- a/packages/ui/src/components/sections/openchamber/OpenCodeCliSettings.tsx
+++ b/packages/ui/src/components/sections/openchamber/OpenCodeCliSettings.tsx
@@ -71,7 +71,15 @@ export const OpenCodeCliSettings: React.FC = () => {
   const handleSaveAndReload = React.useCallback(async () => {
     setIsSaving(true);
     try {
-      await updateDesktopSettings({ opencodeBinary: value.trim() });
+      // Strip a wrapping quote pair (Windows "Copy as path" pastes) — literal
+      // quotes are never part of a real path.
+      const trimmed = value.trim();
+      const unquoted = trimmed.length >= 2
+        && ((trimmed.startsWith('"') && trimmed.endsWith('"'))
+          || (trimmed.startsWith("'") && trimmed.endsWith("'")))
+        ? trimmed.slice(1, -1).trim()
+        : trimmed;
+      await updateDesktopSettings({ opencodeBinary: unquoted });
       await reloadOpenCodeConfiguration({
         message: t('settings.openchamber.opencodeCli.actions.restartingOpenCode'),
         mode: 'projects',
diff --git a/packages/vscode/src/opencode.ts b/packages/vscode/src/opencode.ts
index c7e5cd85..c1f60f73 100644
--- a/packages/vscode/src/opencode.ts
+++ b/packages/vscode/src/opencode.ts
@@ -123,14 +123,40 @@ function isExecutable(filePath: string): boolean {
   }
 }
 
-function shouldUseWindowsShell(binary: string): boolean {
-  if (process.platform !== 'win32') return false;
+// Windows launch spec: .cmd/.bat shims (and bare names, which resolve to .cmd
+// shims via PATHEXT) must run under cmd.exe. Spawn cmd.exe DIRECTLY with the
+// shim path as its own argv element (shell:false) — `shell: true` builds an
+// unquoted command line, so a space-containing path like
+// "C:\Program Files\nodejs\opencode.cmd" broke with
+// "'C:\Program' is not recognized as an internal or external command".
+function resolveWindowsLaunchSpec(binary: string, args: string[]): { binary: string; args: string[] } {
+  if (process.platform !== 'win32') {
+    return { binary, args };
+  }
   const trimmed = (binary || '').trim();
-  if (!trimmed) return true;
   const ext = path.extname(trimmed).toLowerCase();
-  if (ext === '.cmd' || ext === '.bat') return true;
-  // Bare command names often resolve to .cmd shims via PATHEXT.
-  return !ext && !trimmed.includes('\\') && !trimmed.includes('/');
+  const isBatchShim = ext === '.cmd' || ext === '.bat';
+  const isBareName = !ext && !trimmed.includes('\\') && !trimmed.includes('/');
+  if (!isBatchShim && !isBareName) {
+    return { binary: trimmed, args };
+  }
+  return {
+    binary: process.env.ComSpec || 'cmd.exe',
+    args: ['/d', '/s', '/c', 'call', trimmed, ...args],
+  };
+}
+
+// Strip a single wrapping quote pair (Windows "Copy as path" and quoted shell
+// snippets) — literal quotes are never part of a real path and break every
+// executable check.
+function stripWrappingQuotes(value: string): string {
+  const trimmed = (value || '').trim();
+  if (trimmed.length >= 2
+    && ((trimmed.startsWith('"') && trimmed.endsWith('"'))
+      || (trimmed.startsWith("'") && trimmed.endsWith("'")))) {
+    return trimmed.slice(1, -1).trim();
+  }
+  return trimmed;
 }
 
 function appendToPath(dir: string) {
@@ -177,7 +203,7 @@ function normalizeConfiguredOpencodeBinary(raw: unknown): string | null {
   if (typeof raw !== 'string') {
     return null;
   }
-  const trimmed = raw.trim();
+  const trimmed = stripWrappingQuotes(raw);
   if (!trimmed) {
     return null;
   }
@@ -193,7 +219,7 @@ function normalizeConfiguredOpencodeBinary(raw: unknown): string | null {
 }
 
 function isMacOpenCodeAppBundlePath(candidate: string): boolean {
-  return process.platform === 'darwin' && /\/OpenCode\.app\/Contents\/MacOS\/(?:OpenCode|opencode-cli)$/i.test(candidate);
+  return process.platform === 'darwin' && /\/OpenCode(?: Dev| Beta)?\.app\/Contents\/MacOS\/(?:OpenCode(?: Dev| Beta)?|opencode-cli)$/i.test(candidate);
 }
 
 function isWindowsOpenCodeDesktopAppPath(candidate: string): boolean {
@@ -318,7 +344,7 @@ function resolveOpencodeCliPath(): string | null {
     process.env.OPENCHAMBER_OPENCODE_PATH,
     process.env.OPENCHAMBER_OPENCODE_BIN,
   ]
-    .map((v) => (typeof v === 'string' ? v.trim() : ''))
+    .map((v) => (typeof v === 'string' ? stripWrappingQuotes(v) : ''))
     .filter(Boolean);
 
   for (const candidate of explicit) {
@@ -357,6 +383,10 @@ function resolveOpencodeCliPath(): string | null {
       path.join(npmDir, 'opencode.exe'),
       path.join(npmDir, 'opencode.cmd'),
       path.join(npmDir, 'opencode.bat'),
+      // System-wide Node installer keeps the global npm prefix here
+      // (npm i -g opencode-ai → opencode.cmd shim).
+      path.join(process.env.ProgramFiles || 'C:\\Program Files', 'nodejs', 'opencode.cmd'),
+      path.join(userProfile, 'scoop', 'shims', 'opencode.exe'),
       path.join(userProfile, 'scoop', 'shims', 'opencode.cmd'),
       path.join(programData, 'chocolatey', 'bin', 'opencode.exe'),
       path.join(programData, 'chocolatey', 'bin', 'opencode.cmd'),
@@ -393,6 +423,7 @@ function resolveOpencodeCliPath(): string | null {
       const result = spawnSync('where', ['opencode'], {
         encoding: 'utf8',
         stdio: ['ignore', 'pipe', 'pipe'],
+        windowsHide: true,
       });
       if (result.status === 0) {
         const lines = (result.stdout || '')
@@ -632,14 +663,13 @@ async function spawnManagedOpenCodeServer(
   port: number,
   timeoutMs: number
 ): Promise<{ url: string; close: () => void }> {
-  const binary = (process.env.OPENCODE_BINARY || 'opencode').trim() || 'opencode';
-  const args = ['serve', '--hostname', '127.0.0.1', '--port', String(port)];
-  const child = spawn(binary, args, {
+  const binary = stripWrappingQuotes(process.env.OPENCODE_BINARY || 'opencode') || 'opencode';
+  const launch = resolveWindowsLaunchSpec(binary, ['serve', '--hostname', '127.0.0.1', '--port', String(port)]);
+  const child = spawn(launch.binary, launch.args, {
     cwd: workingDirectory,
     env: { ...process.env },
     stdio: ['ignore', 'pipe', 'pipe'],
     windowsHide: true,
-    shell: shouldUseWindowsShell(binary),
   });
 
   const url = await new Promise<string>((resolve, reject) => {
diff --git a/packages/web/server/lib/opencode/env-runtime.js b/packages/web/server/lib/opencode/env-runtime.js
index 7e4cf9d6..154608d7 100644
--- a/packages/web/server/lib/opencode/env-runtime.js
+++ b/packages/web/server/lib/opencode/env-runtime.js
@@ -317,6 +317,19 @@ export const createOpenCodeEnvRuntime = (deps) => {
     state.resolvedWslDistro = null;
   };
 
+  // Strip a single wrapping quote pair (Windows "Copy as path" and quoted
+  // shell snippets) — literal quotes are never part of a real path and break
+  // every executable check.
+  const stripWrappingQuotes = (value) => {
+    const trimmed = typeof value === 'string' ? value.trim() : '';
+    if (trimmed.length >= 2
+      && ((trimmed.startsWith('"') && trimmed.endsWith('"'))
+        || (trimmed.startsWith("'") && trimmed.endsWith("'")))) {
+      return trimmed.slice(1, -1).trim();
+    }
+    return trimmed;
+  };
+
   const resolveOpencodeCliPath = () => {
     const explicit = [
       process.env.OPENCODE_BINARY,
@@ -324,7 +337,7 @@ export const createOpenCodeEnvRuntime = (deps) => {
       process.env.OPENCHAMBER_OPENCODE_PATH,
       process.env.OPENCHAMBER_OPENCODE_BIN,
     ]
-      .map((v) => (typeof v === 'string' ? v.trim() : ''))
+      .map(stripWrappingQuotes)
       .filter(Boolean);
 
     for (const candidate of explicit) {
@@ -353,6 +366,7 @@ export const createOpenCodeEnvRuntime = (deps) => {
       path.join(home, 'bin', 'opencode'),
       '/opt/homebrew/bin/opencode',
       '/usr/local/bin/opencode',
+      '/home/linuxbrew/.linuxbrew/bin/opencode',
       '/usr/bin/opencode',
       '/bin/opencode',
     ];
@@ -363,10 +377,16 @@ export const createOpenCodeEnvRuntime = (deps) => {
       const localAppData = process.env.LOCALAPPDATA || '';
       const programData = process.env.ProgramData || 'C:\\ProgramData';
 
+      const programFiles = process.env.ProgramFiles || 'C:\\Program Files';
+
       return [
         path.join(userProfile, '.opencode', 'bin', 'opencode.exe'),
         path.join(userProfile, '.opencode', 'bin', 'opencode.cmd'),
         path.join(appData, 'npm', 'opencode.cmd'),
+        // System-wide Node installer keeps the global npm prefix here
+        // (npm i -g opencode-ai → opencode.cmd shim).
+        path.join(programFiles, 'nodejs', 'opencode.cmd'),
+        path.join(userProfile, 'scoop', 'shims', 'opencode.exe'),
         path.join(userProfile, 'scoop', 'shims', 'opencode.cmd'),
         path.join(programData, 'chocolatey', 'bin', 'opencode.exe'),
         path.join(programData, 'chocolatey', 'bin', 'opencode.cmd'),
@@ -818,6 +838,16 @@ export const createOpenCodeEnvRuntime = (deps) => {
       }
     }
 
+    // Final fallback: never hand a raw .cmd/.bat to spawn(shell:false) — cmd
+    // shims need cmd.exe, and unquoted space-containing paths break there.
+    if (WINDOWS_BATCH_EXTENSIONS.has(ext)) {
+      return {
+        binary: process.env.ComSpec || 'cmd.exe',
+        args: ['/d', '/s', '/c', 'call', fallbackBinary],
+        wrapperType: 'cmd-wrapper',
+      };
+    }
+
     return { binary: fallbackBinary, args: [], wrapperType: null };
   };
 
@@ -873,7 +903,7 @@ export const createOpenCodeEnvRuntime = (deps) => {
     if (process.platform !== 'darwin' || typeof candidate !== 'string') {
       return false;
     }
-    return /\/OpenCode\.app\/Contents\/MacOS\/(?:OpenCode|opencode-cli)$/i.test(candidate);
+    return /\/OpenCode(?: Dev| Beta)?\.app\/Contents\/MacOS\/(?:OpenCode(?: Dev| Beta)?|opencode-cli)$/i.test(candidate);
   };
 
   const isKnownOpenCodeDesktopAppPath = (candidate) => isMacOpenCodeAppBundlePath(candidate)
diff --git a/packages/web/server/lib/opencode/settings-normalization-runtime.js b/packages/web/server/lib/opencode/settings-normalization-runtime.js
index f237e559..a5343633 100644
--- a/packages/web/server/lib/opencode/settings-normalization-runtime.js
+++ b/packages/web/server/lib/opencode/settings-normalization-runtime.js
@@ -17,7 +17,15 @@ export const createSettingsNormalizationRuntime = (dependencies) => {
       return value;
     }
 
-    const trimmed = value.trim();
+    let trimmed = value.trim();
+    // Paths pasted from Windows "Copy as path" (or quoted shell snippets)
+    // arrive wrapped in quotes — a literal quote character can never be part
+    // of a real path, and it breaks every fs.stat/executable check.
+    if (trimmed.length >= 2
+      && ((trimmed.startsWith('"') && trimmed.endsWith('"'))
+        || (trimmed.startsWith("'") && trimmed.endsWith("'")))) {
+      trimmed = trimmed.slice(1, -1).trim();
+    }
     if (!trimmed) {
       return trimmed;
     }