Hi for all. I Have a RB411U with Fw 3.30. Can i upgrade to 4.x??

Thanks.

Yes, read the manual below for how, pay specific attention to the section linked to.
http://wiki.mikrotik.com/wiki/Manual:Up ... nse_issues

Thanks for your answer. I have a problem with my board. Before you say me this, i was write in console: "/system routerboard upgrade", and now, my RB411U doesn't boot. Please, see my other post:

http://forum.mikrotik.com/viewtopic.php?f=3&t=49825

Thanks.

Netinstall is your friend