I just downloaded the lastest Version of Ubuntu13.04 from the official website(of course it is amd64)and my Computer is the ASUS-A45V Laptop.I used the universal usb installer to creater a boot usb disk for installing ubuntu.And first i tried to use the first default option to install it(that means i let ubuntu to do all the things itself,and i have Win7 installed on my HDD),and all the things seems runs very good.but, then when i reboot and try to start ubuntu.It told me that "Faild to mount /boot/efi, type S to skip it, or type M to fix it manually"and then i check the /boot/efi folder ,and find that there is nothing in it! And then i tried to install it manually,but got the same result. Whats the problem? How can i fix it?and whats more, Boot-Repair can only bring my Win7 loader back in the Grub list but the formal efi loader of Win7 has been overwrited into Grub by Ubuntu. How can i restore it?
First, it was Boot Repair, not Ubuntu's installer, that replaced the Windows boot loader with another copy of GRUB. Boot Repair does this because it's the only available workaround for some buggy BIOSes that will launch the Windows boot loader but not a Linux boot loader; but IMHO, Boot Repair is far too quick to resort to this solution, which is an inelegant (albeit occasionally necessary) hack. IIRC, there's an option in Boot Repair to undo this change. If you can't find it, you can do the same thing manually by renaming files. The Microsoft boot loader should be
You mentioned Windows 7, but be aware that Windows 8 doesn't use a normal shutdown by default. Instead, it uses a "fast startup" feature that's more like a suspend-to-disk operation. One consequence of this is that filesystems are left in an inconsistent state. I've heard of this feature causing problems with the ESP on some computers, which is why I mention it. When dual-booting with Windows 8, you should disable the "fast startup" feature, as described here. Even in Windows 7, you might see something similar if you used a suspend-to-disk feature or otherwise did not shut down cleanly.