Index: sources/device/DeviceController.cpp
===================================================================
diff -u -r3b402a2cfb9e673bf0bac3fcc8eeee75a0adc475 -r4ef7cb77805b64ac89966a9581cdc111520f21d1
--- sources/device/DeviceController.cpp	(.../DeviceController.cpp)	(revision 3b402a2cfb9e673bf0bac3fcc8eeee75a0adc475)
+++ sources/device/DeviceController.cpp	(.../DeviceController.cpp)	(revision 4ef7cb77805b64ac89966a9581cdc111520f21d1)
@@ -978,11 +978,19 @@
 void DeviceController::onAttributeRequest(const DeviceUSBMountRequestData &vData)
 {
     Q_UNUSED(vData)
-    // TODO - VY ideally we don't have this function, but macros used needs it declared
+    requestUSBMount(vData.isUnmountRequest, vData.usbDrive);
 }
+
+/*!
+ * \brief   DeviceController::requestUSBMount
+ * \details Calls the Usb unmount/mount script
+ * \param   vIsUnmount - indicate if the request is for mounting or unmounting
+ * \param   vUSBDrive - the path to the USB drive
+ */
 void DeviceController::requestUSBMount(bool vIsUnmount, const QString vUSBDrive)
 {
     _deviceUSBMountRequest._data.isUnmountRequest = vIsUnmount;
+    _deviceUSBMountRequest._data.usbDrive         = vUSBDrive; // not necessary, but to be consistent
 
     // ----- check that script exists.
     QString script;
@@ -1021,18 +1029,23 @@
     if ( vStatus )  vExitCode   = Device::DeviceError::eDevice_Scripts_Error_Status;
     else            deviceInfo  = _processUSBMount.readAll();
     model.fromByteArray( deviceInfo, &vExitCode );
-    // DEBUG: qDebug() << model._data.mMessage << deviceInfo;
     didAttributeResponse(model.data());
     LOG_APPED_UI(model.data().mMessage);
 
+    // Re-evaluate the USB space available - need to call this here to avoid
+    // visual lag caused by waiting to call this function on the timer timeout
+    usbSpaceCheck();
+
+    QString usbDrive = _deviceUSBMountRequest._data.usbDrive;
     if(_deviceUSBMountRequest._data.isUnmountRequest) {
         _mounted = false;
-//        LOG_DEBUG(QString("USB drive %2 unmounted").arg(_deviceUSBMountRequest._data.usbDrive));
+        LOG_DEBUG(QString("USB drive %2 unmounted").arg(usbDrive));
         emit didUSBDriveUmount();
     } else {
+        if(vStatus) {   usbError(usbDrive);   return;  } // log error and exit
         _mounted = true;
         _removed = false;
-//        LOG_DEBUG(QString("USB flash drive %1 has been mounted on %2").arg(_deviceUSBMountRequest._data.usbDrive).arg(_deviceUSBMountRequest._data.usbMountPoint));
+        LOG_DEBUG(QString("USB flash drive %1 has been mounted on %2").arg(usbDrive).arg(USB_Mount_Point));
         emit didUSBDriveMount();
     }
 }