diff --git a/src/system/kernel/disk_device_manager/KDiskDeviceManager.cpp b/src/system/kernel/disk_device_manager/KDiskDeviceManager.cpp
index 76b43c91e0..6fb1bf28e0 100644
--- a/src/system/kernel/disk_device_manager/KDiskDeviceManager.cpp
+++ b/src/system/kernel/disk_device_manager/KDiskDeviceManager.cpp
@@ -1373,6 +1373,10 @@ KDiskDeviceManager::_ScanPartition(KPartition* partition,
 		return B_OK;
 	}
 
+	// This happens with some copy protected CDs. Just ignore the partition...
+	if (partition->Offset() < 0)
+		return B_BAD_DATA;
+
 	DBG(
 		KPath partitionPath;
 		partition->GetPath(&partitionPath);