diff --git a/affinity/src/main/java/net/openhft/affinity/LockCheck.java b/affinity/src/main/java/net/openhft/affinity/LockCheck.java
index 5d3db1535..2953637c3 100644
--- a/affinity/src/main/java/net/openhft/affinity/LockCheck.java
+++ b/affinity/src/main/java/net/openhft/affinity/LockCheck.java
@@ -78,6 +78,9 @@ private synchronized static boolean isLockFree(int id) {
     }
 
     public static int getProcessForCpu(int core) throws IOException {
+        if (!canOSSupportOperation())
+            return EMPTY_PID;
+
         String meta = lockChecker.getMetaInfo(core);
 
         if (meta != null && !meta.isEmpty()) {
diff --git a/affinity/src/test/java/net/openhft/affinity/FileLockLockCheckTest.java b/affinity/src/test/java/net/openhft/affinity/FileLockLockCheckTest.java
index b155e4999..6be18c5d7 100644
--- a/affinity/src/test/java/net/openhft/affinity/FileLockLockCheckTest.java
+++ b/affinity/src/test/java/net/openhft/affinity/FileLockLockCheckTest.java
@@ -96,4 +96,12 @@ public void lockFileDeletedWhileHeld() throws Exception {
         lockFile = lockChecker.doToFile(cpu);
         Assert.assertTrue("Lock file should be recreated", lockFile.exists());
     }
+
+    @Test
+    public void getProcessForCpuReturnsEmptyPidWhenNoFile() throws IOException {
+        int freeCpu = 99;
+        File lockFile = lockChecker.doToFile(freeCpu);
+        Assert.assertFalse(lockFile.exists());
+        Assert.assertEquals(Integer.MIN_VALUE, LockCheck.getProcessForCpu(freeCpu));
+    }
 }