If the software update contains kernel update I don't update I fresh flash or it can end up in a bootloop. Or it could be skin/ or plugin used on your box is not compatible with something contained in update. If it was me I would reflash fresh image using usb stick and go through setup from scratch. As long as you have a copy of things like line details it is probably quickest way. Someone else may be able to help with way to determine exactly what is causing it.
Octagon sf4008 normally has no issue when updating online but when it goes wrong it can become corrupted and stop you usb flashing as well. Forum rules stop me linking you to another site but google unable to flash octagon sf4008 by usb and go to first link and read whole thread