I recently swapped the 100Gb hard drive that my laptop came with for a 320Gb model. I kept running out of space and deleting operating system components that I wasn't using, which is all very well except that when I tried to install Vista SP2 it complained that important files were missing. The SP2 installer doesn't really need those files either, it just does an integrity check.
After having installed the new drive I started to install Windows and then discovered that my laptop's DVD drive was in bad shape. It could read CDs fine but not DVDs at all.
I had read that it was possible to install Vista from a USB key so I tried this. Unfortunately the only USB key I have handy is a 1Gb one and Vista claims it needs a 4Gb one to install from. There doesn't appear to be anywhere close by that sells USB keys.
I wondered if it was possible to boot from the USB key, copy the required files to the hard drive over the network using the preinstallation environment and then install from the hard drive. With a bit of fiddling I got it to work, and here is how I did it.
- Format the USB key to NTFS, copy the files over but excluding install.wim. This only takes about 256Mb. Make the key bootable with "bootsect /nt60" and boot from it.
- Choose "repair" at the computer and open a command prompt. Use diskpart to partition and format the drive.
- Now we need to get the installation files onto the hard drive, including install.wim. We can get TCP/IP networking up and running with netsh but the Vista preinstallation environment doesn't include SMB file sharing. It does however include the ftp client, so we can set up a small FTP server another machine and then ftp install.wim over. The rest of the files can just be copied from the USB key.
- The next part is tricky - we need to convince the installer to run from the hard drive and also install to the hard drive. If we make the hard drive bootable the same way we made the USB key bootable and try to boot from it, the installer gets very confused and gets stuck in a loop after a couple of reboots. However, I hit upon another way which does work. Unmount the USB key and the hard drive with "mountvol /d" and then mount the hard drive with the same drive letter that was being used for the USB key. Then run "setup" and install Vista as normal.
Addendum: I tried to do this again with a new computer I built, but the Vista preinstallation environment didn't have drivers for my network card. Obviously if this is the case, another method must be used.