Same here. I have taken all the suggested steps but up to now, Ive been receiving the same "server undergoing maintenance" error.
I tried changing DNS to google dns 8.8.8.8. It did work when I first did it a few months back but since the sept patch, everything got screwed.
Another thing I did noticed is that eventhough theres nothing running, the MWO REPAIR TOOL KIT is running when I checked Task Manager. No matter how many times I press end task", it wont get deleted. I have to reboot so it would go away.