diff -r 5af6c74cd793 -r af6ec97d9189 userlibandfileserver/fileserver/shostmassstorage/server/controller/cusbhostmsdevicethread.cpp
--- a/userlibandfileserver/fileserver/shostmassstorage/server/controller/cusbhostmsdevicethread.cpp	Wed Jun 23 11:59:44 2010 +0100
+++ b/userlibandfileserver/fileserver/shostmassstorage/server/controller/cusbhostmsdevicethread.cpp	Wed Jun 23 12:52:28 2010 +0100
@@ -308,6 +308,9 @@
             }
 		return;
 	case EUsbHostMsUnRegisterInterface:
+		// Check whether all luns have got uninitialised. 
+		for(TInt i = 0, j = iUsbHostMsDevice->GetMaxLun(); i <= j; i++)
+			TRAP_IGNORE(iUsbHostMsDevice->RemoveLunL(i));
 		TRAP(ret, UnRegisterInterfaceL(aMessage));
 		break;
 	case EUsbHostMsRegisterLun: