Install windows from a network location

First create a win pe image and either set up a pxe boot server or just boot from dvd or usb.

You will end up with a cmd prompt :
X:\windows\system32\>wpeinit

Map the location where you have the windows image :

net use n: \\networkpc\sharename passwords /user:username
cd n:\windows7
setup.exe

If you run into an error "autorun.dll" could not be loaded or is corrupt setup can not continue error code (0xC1). This means your version of WinPE is mismatched with your Windows ISO. Type ver at the WinPE prompt.

|   ver    | Win PE Version | Matching Windows ISO | 
----------------------------------------------------
| 6.0.6*** |     2.*        |    Windows Vista     |
| 6.1.7600 |     3.0        |      Windows 7       |
| 6.1.7601 |     3.1        |    Windows 7 SP1     |
| 6.2.9200 |     4.0        |      Windows 8       |
| 6.3.9600 |     5.0        |     Windows 8.1      |