diff --git a/tests/helpers/isolated-codex-home.ts b/tests/helpers/isolated-codex-home.ts
index 975e8e81c..17273755e 100644
--- a/tests/helpers/isolated-codex-home.ts
+++ b/tests/helpers/isolated-codex-home.ts
@@ -1,6 +1,7 @@
-import { mkdtempSync, rmSync, writeFileSync } from "node:fs";
+import { mkdtempSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
+import { removeTreeWithRetry } from "./remove-tree";
 
 export interface IsolatedCodexHome {
   path: string;
@@ -18,7 +19,7 @@ export function installIsolatedCodexHome(prefix = "ocx-codex-home-"): IsolatedCo
     restore() {
       if (previousCodexHome === undefined) delete process.env.CODEX_HOME;
       else process.env.CODEX_HOME = previousCodexHome;
-      rmSync(path, { recursive: true, force: true });
+      removeTreeWithRetry(path);
     },
   };
 }
diff --git a/tests/helpers/remove-tree.ts b/tests/helpers/remove-tree.ts
new file mode 100644
index 000000000..53e36a584
--- /dev/null
+++ b/tests/helpers/remove-tree.ts
@@ -0,0 +1,32 @@
+import { rmSync } from "node:fs";
+
+const TRANSIENT_REMOVE_CODES = new Set(["EPERM", "EBUSY", "ENOTEMPTY"]);
+const REMOVE_ATTEMPTS = 50;
+const REMOVE_RETRY_DELAY_MS = 50;
+
+type RemoveTreeWithRetryOptions = Readonly<{
+  remove?: (path: string) => void;
+  sleep?: (milliseconds: number) => void;
+}>;
+
+/** Retry only Windows filesystem-release races; preserve every other cleanup failure. */
+export function removeTreeWithRetry(
+  path: string,
+  options: RemoveTreeWithRetryOptions = {},
+): void {
+  const remove = options.remove ?? (target => rmSync(target, { recursive: true, force: true }));
+  const sleep = options.sleep ?? Bun.sleepSync;
+
+  for (let attempt = 1; attempt <= REMOVE_ATTEMPTS; attempt += 1) {
+    try {
+      remove(path);
+      return;
+    } catch (error) {
+      const code = error && typeof error === "object" && "code" in error
+        ? String(error.code)
+        : "";
+      if (!TRANSIENT_REMOVE_CODES.has(code) || attempt === REMOVE_ATTEMPTS) throw error;
+      sleep(REMOVE_RETRY_DELAY_MS);
+    }
+  }
+}
diff --git a/tests/remove-tree-helper.test.ts b/tests/remove-tree-helper.test.ts
new file mode 100644
index 000000000..f7c4cb4b1
--- /dev/null
+++ b/tests/remove-tree-helper.test.ts
@@ -0,0 +1,51 @@
+import { describe, expect, test } from "bun:test";
+import { removeTreeWithRetry } from "./helpers/remove-tree";
+
+function codedError(code: string, message = code): Error & { code: string } {
+  return Object.assign(new Error(message), { code });
+}
+
+describe("removeTreeWithRetry", () => {
+  test.each(["EPERM", "EBUSY", "ENOTEMPTY"])("retries transient %s failures", code => {
+    let removeCalls = 0;
+    const sleeps: number[] = [];
+
+    removeTreeWithRetry("ignored", {
+      remove: () => {
+        removeCalls += 1;
+        if (removeCalls < 3) throw codedError(code);
+      },
+      sleep: milliseconds => sleeps.push(milliseconds),
+    });
+
+    expect(removeCalls).toBe(3);
+    expect(sleeps).toEqual([50, 50]);
+  });
+
+  test("rethrows non-transient failures immediately", () => {
+    const error = codedError("EACCES", "denied");
+    let sleeps = 0;
+
+    expect(() => removeTreeWithRetry("ignored", {
+      remove: () => { throw error; },
+      sleep: () => { sleeps += 1; },
+    })).toThrow(error);
+    expect(sleeps).toBe(0);
+  });
+
+  test("rethrows the final transient failure without an extra sleep", () => {
+    const error = codedError("EBUSY", "still locked");
+    let removeCalls = 0;
+    let sleeps = 0;
+
+    expect(() => removeTreeWithRetry("ignored", {
+      remove: () => {
+        removeCalls += 1;
+        throw error;
+      },
+      sleep: () => { sleeps += 1; },
+    })).toThrow(error);
+    expect(removeCalls).toBe(50);
+    expect(sleeps).toBe(49);
+  });
+});
diff --git a/tests/server-rate-limit-retry-e2e.test.ts b/tests/server-rate-limit-retry-e2e.test.ts
index 6a6d7f4c6..467f6ca52 100644
--- a/tests/server-rate-limit-retry-e2e.test.ts
+++ b/tests/server-rate-limit-retry-e2e.test.ts
@@ -1,5 +1,5 @@
 import { afterEach, beforeEach, describe, expect, test } from "bun:test";
-import { mkdtempSync, rmSync } from "node:fs";
+import { mkdtempSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { saveConfig } from "../src/config";
@@ -7,6 +7,7 @@ import { clearKeyCooldowns } from "../src/providers/key-failover";
 import { startServer } from "../src/server";
 import type { OcxConfig } from "../src/types";
 import { installIsolatedCodexHome, type IsolatedCodexHome } from "./helpers/isolated-codex-home";
+import { removeTreeWithRetry } from "./helpers/remove-tree";
 
 let testDir = "";
 let previousHome: string | undefined;
@@ -25,7 +26,7 @@ afterEach(() => {
   else process.env.OPENCODEX_HOME = previousHome;
   isolatedCodexHome?.restore();
   isolatedCodexHome = null;
-  if (testDir) rmSync(testDir, { recursive: true, force: true });
+  if (testDir) removeTreeWithRetry(testDir);
   clearKeyCooldowns();
 });
 
@@ -100,8 +101,11 @@ describe("server same-target 429 retry (end-to-end)", () => {
       expect(seenHeaders[0]).toEqual(seenHeaders[1]);
       expect(seenHeaders[1]).toEqual(seenHeaders[2]);
     } finally {
-      server?.stop(true);
-      globalThis.fetch = originalFetch;
+      try {
+        await server?.stop(true);
+      } finally {
+        globalThis.fetch = originalFetch;
+      }
     }
   });
 
@@ -144,8 +148,11 @@ describe("server same-target 429 retry (end-to-end)", () => {
       expect(json.error?.type).toBe("rate_limit_error");
       expect(sends).toBe(1);
     } finally {
-      server?.stop(true);
-      globalThis.fetch = originalFetch;
+      try {
+        await server?.stop(true);
+      } finally {
+        globalThis.fetch = originalFetch;
+      }
     }
   });
 
@@ -186,8 +193,11 @@ describe("server same-target 429 retry (end-to-end)", () => {
       expect(res.status).toBe(429);
       expect(sends).toBe(2);
     } finally {
-      server?.stop(true);
-      globalThis.fetch = originalFetch;
+      try {
+        await server?.stop(true);
+      } finally {
+        globalThis.fetch = originalFetch;
+      }
     }
   });
 
@@ -240,8 +250,11 @@ describe("server same-target 429 retry (end-to-end)", () => {
         "Bearer key-beta-444555666777",
       ]);
     } finally {
-      server?.stop(true);
-      globalThis.fetch = originalFetch;
+      try {
+        await server?.stop(true);
+      } finally {
+        globalThis.fetch = originalFetch;
+      }
     }
   });
 
@@ -303,8 +316,11 @@ describe("server same-target 429 retry (end-to-end)", () => {
       expect(seenBodies).toHaveLength(2);
       expect(seenBodies[0]).toBe(seenBodies[1]);
     } finally {
-      server?.stop(true);
-      globalThis.fetch = originalFetch;
+      try {
+        await server?.stop(true);
+      } finally {
+        globalThis.fetch = originalFetch;
+      }
     }
   });
 
@@ -351,8 +367,11 @@ describe("server same-target 429 retry (end-to-end)", () => {
       // have replayed on the second key too (4+ sends).
       expect(sends).toBe(3);
     } finally {
-      server?.stop(true);
-      globalThis.fetch = originalFetch;
+      try {
+        await server?.stop(true);
+      } finally {
+        globalThis.fetch = originalFetch;
+      }
     }
   });
 });