diff --git a/CHANGELOG.md b/CHANGELOG.md
index 93430dfdbc..d9f734d3d4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -61,6 +61,10 @@ between releases do not reach them. Remote-PC runtime bundles are versioned sepa
   ([#724](https://github.com/devswha/herdr-web-ui/pull/724))
 
 ### Fixed
+- Codex conversations on Windows resolve the transcript even when the pane's working directory
+  uses different letter casing from Codex's stored path. The lookup verifies the directory on
+  disk before considering its canonical spelling, so another pane's chat is not substituted.
+  ([#740](https://github.com/devswha/herdr-web-ui/pull/740) by @antonydoyle)
 - The browser demo keeps each row's own split when resizing a grid and keeps deeply split
   panes visible and resizable. ([#726](https://github.com/devswha/herdr-web-ui/pull/726))
 - Workspace and tab changes, pane moves and layout updates made in herdr's terminal UI
diff --git a/server/codex.ts b/server/codex.ts
index 7381695d68..adee438f70 100644
--- a/server/codex.ts
+++ b/server/codex.ts
@@ -466,13 +466,21 @@ export function directoryKey(cwd: string): string {
 
 /** Whether two cwds are one directory by `directoryKey`; POSIX ones only when they are equal. */
 export function sameDirectory(left: string, right: string): boolean {
-  return directoryKey(left) === directoryKey(right);
+  if (directoryKey(left) === directoryKey(right)) return true;
+  if (process.platform !== "win32") return false;
+  try {
+    // bigint: a Windows file ID is 64-bit, and two of them can round to one number
+    const a = statSync(left, { bigint: true });
+    const b = statSync(right, { bigint: true });
+    return a.isDirectory() && b.isDirectory() && a.dev === b.dev && a.ino === b.ino;
+  } catch { return false; }
 }
 
 /** The other Codex panes herdr shows in this pane's directory, in any spelling `sameDirectory` takes. */
 export function codexPeersIn(panes: readonly HerdrPane[], paneId: string, cwd: string): HerdrPane[] {
-  return panes.filter((pane) => pane.pane_id !== paneId && pane.cwd != null && sameDirectory(pane.cwd, cwd)
-    && (pane.agent ?? pane.agent_session?.agent) === "codex");
+  // the agent first: sameDirectory can ask the file system, and only Codex panes need it
+  return panes.filter((pane) => pane.pane_id !== paneId && (pane.agent ?? pane.agent_session?.agent) === "codex"
+    && pane.cwd != null && sameDirectory(pane.cwd, cwd));
 }
 
 /**
@@ -481,7 +489,14 @@ export function codexPeersIn(panes: readonly HerdrPane[], paneId: string, cwd: s
  * stays on Codex's own binary cwd index.
  */
 export function storedCwdCondition(cwd: string): { where: string; params: string[] } {
-  const params = [...new Set(storedCwds(cwd).flatMap((spelling) => {
+  // Windows resolves an existing directory to its on-disk casing. Herdr may report the
+  // shell's spelling while Codex stores the canonical spelling in its binary cwd index.
+  // Keep both: the original is needed when Codex recorded it before a rename or via a link.
+  let canonical = cwd;
+  if (process.platform === "win32") {
+    try { canonical = realpathSync.native(cwd); } catch { /* A removed cwd still has its reported spelling. */ }
+  }
+  const params = [...new Set([cwd, canonical].flatMap((path) => storedCwds(path)).flatMap((spelling) => {
     const drive = /^((?:\\\\\?\\)?)([A-Za-z])(:\\.*)$/s.exec(spelling);
     return drive ? [`${drive[1]}${drive[2]!.toUpperCase()}${drive[3]}`, `${drive[1]}${drive[2]!.toLowerCase()}${drive[3]}`] : [spelling];
   }))];
diff --git a/server/windows-native.test.ts b/server/windows-native.test.ts
index 99b273f5ab..fd5ea8d6fe 100644
--- a/server/windows-native.test.ts
+++ b/server/windows-native.test.ts
@@ -11,7 +11,9 @@ import { tmpdir } from "node:os";
 import { join } from "node:path";
 
 import { claudeProcessSession, forgetClaudeSessions, processClaudeConfigDir } from "./claude-store.ts";
-import { codexRolloutPath } from "./codex.ts";
+import { Database } from "bun:sqlite";
+
+import { codexRolloutPath, directoryKey, sameDirectory, storedCwdCondition } from "./codex.ts";
 import { gjcSessionFile, storeRelative } from "./gjc-runtime.ts";
 import { descendantArgv, windowsProcessTable } from "./windows-processes.ts";
 import { windowsHost } from "./remote-host.ts";
@@ -122,6 +124,25 @@ it.skipIf(!onWindows)("reads a Codex rollout path stored with the \\\\?\\ prefix
   } finally { rmSync(root, { recursive: true, force: true }); }
 });
 
+it.skipIf(!onWindows)("finds Codex's thread under the on-disk casing when herdr reports another spelling of the directory (#740)", () => {
+  const root = realpathSync.native(mkdtempSync(join(tmpdir(), "herdr-codex-cwd-")));
+  mkdirSync(join(root, "Recorde"));
+  const reported = join(root, "recorde");
+  const canonical = realpathSync.native(reported);
+  const db = new Database(":memory:");
+  try {
+    // the two spellings are only one directory to the file system, not to directoryKey
+    expect(directoryKey(reported)).not.toBe(directoryKey(canonical));
+    db.run("CREATE TABLE threads (id TEXT, cwd TEXT)");
+    db.run("INSERT INTO threads VALUES (?, ?)", ["own", `\\\\?\\${canonical}`]);
+    const { where, params } = storedCwdCondition(reported);
+    expect(db.query<{ id: string }, string[]>(`SELECT id FROM threads WHERE ${where}`).all(...params)).toEqual([{ id: "own" }]);
+    expect(sameDirectory(reported, canonical)).toBe(true);
+    mkdirSync(join(root, "Other"));
+    expect(sameDirectory(reported, join(root, "Other"))).toBe(false);
+  } finally { db.close(); rmSync(root, { recursive: true, force: true }); }
+});
+
 it.skipIf(!onWindows)("finds a Claude's own store from the start it records, which the process table repeats", async () => {
   const home = realpathSync(mkdtempSync(join(tmpdir(), "herdr-claude-native-")));
   const serverConfigDir = process.env["CLAUDE_CONFIG_DIR"];