diff --git a/src/shared/utils/machineId.ts b/src/shared/utils/machineId.ts
index db0dfad80e..1b4837aad4 100644
--- a/src/shared/utils/machineId.ts
+++ b/src/shared/utils/machineId.ts
@@ -57,9 +57,10 @@ function getMachineIdRaw(): string {
   }
 
   // Strategy 2: macOS — ioreg IOPlatformUUID
+  // Skip when DISABLE_IOREG_STRATEGY=1 so tests can reach Strategy 4/5 on darwin.
   try {
-    if (process.platform !== "darwin") {
-      throw new Error("Not macOS");
+    if (process.platform !== "darwin" || process.env.DISABLE_IOREG_STRATEGY === "1") {
+      throw new Error("Not macOS or ioreg disabled");
     }
     const output = execSync("ioreg -rd1 -c IOPlatformExpertDevice", {
       encoding: "utf8",
diff --git a/tests/unit/shared/machineId.test.ts b/tests/unit/shared/machineId.test.ts
index cde9b9a4f6..97cc7b7b05 100644
--- a/tests/unit/shared/machineId.test.ts
+++ b/tests/unit/shared/machineId.test.ts
@@ -30,6 +30,10 @@ function disableWindowsRegistryStrategy(): () => void {
   process.env.SystemRoot = "Z:\\NonExistent";
   process.env.windir = "Z:\\NonExistent";
 
+  // Also disable macOS ioreg strategy so Strategy 4/5 can be reached on darwin.
+  const origDisableIoreg = process.env.DISABLE_IOREG_STRATEGY;
+  process.env.DISABLE_IOREG_STRATEGY = "1";
+
   const origReadFileSync = fs.readFileSync;
   fs.readFileSync = (filePath: string, encoding: string) => {
     if (filePath === "/etc/machine-id" || filePath === "/var/lib/dbus/machine-id") {
@@ -57,6 +61,11 @@ function disableWindowsRegistryStrategy(): () => void {
     } else {
       delete process.env.windir;
     }
+    if (origDisableIoreg !== undefined) {
+      process.env.DISABLE_IOREG_STRATEGY = origDisableIoreg;
+    } else {
+      delete process.env.DISABLE_IOREG_STRATEGY;
+    }
     fs.readFileSync = origReadFileSync;
     childProcess.execSync = origExecSync;
   };