WinPE 3.0 contains the iSCSI initiator driver (msiscsi.sys) by default, and it will connect to an iSCSI target if one was 'sanhooked' (assuming it has inbox NIC drivers that matches your hardware, or such drivers were loaded later using drvload.exe). While this may be enough to start an installation, sometimes you may want to be able to connect to iSCSI targets using the iSCSI command line interface (iscsicli.exe) or control panel (iscsicpl.exe).

The Microsoft iSCSI software initiator user guide contains instructions on how to perform integration of these components to WinPE 2.x, However, with the release of WAIK version 3.0 for Windows 7, those instructions no longer apply. Below are the instructions for creating a WinPE 3.x ISO with those iSCSI components.

1. Download and install WAIK 3.0 (http://www.microsoft.com/en-us/download/details.aspx?id=5753).

2. Enter the 'Deployment Tools Command Promt' (Start > Programs > Microsoft Windows AIK > Deployment Tools Command Promt).

3. Use copype.cmd to create a working directory for the desired architecture, the syntax is:

copype <architecture> <destination>
example (32-bit):
copype x86 C:\winpe_x86
example (64-bit):
copype amd64 C:\winpe_x64

4. Move winpe.wim from the destination directory to the ISO\sources subdirectory, and change its name to boot.wim.

example:
MOVE C:\winpe_x86\winpe.wim C:\winpe_x86\ISO\sources\boot.wim

5. Mount the latter wim image:

example:
imagex /mountrw C:\winpe_x86\ISO\sources\boot.wim 1 C:\winpe_x86\mount

6. Copy the following files from an existing Windows 7 installation (of the same architecture) to the mounted image:

Windows\System32\iscsicli.exe
Windows\System32\iscsicpl.dll
Windows\System32\iscsicpl.exe
Windows\System32\iscsidsc.dll
Windows\System32\iscsied.dll
Windows\System32\iscsiexe.dll
Windows\System32\iscsilog.dll
Windows\System32\iscsium.dll
Windows\System32\iscsiwmi.dll
Windows\System32\en-us\iscsicli.exe.mui
Windows\System32\en-us\iscsicpl.dll.mui
Windows\System32\en-us\iscsicpl.exe.mui
Windows\System32\en-us\iscsidsc.dll.mui
Windows\System32\en-us\iscsiexe.dll.mui
Windows\System32\en-us\iscsilog.dll.mui

7. Use regedit to load the system (WINDOWS\system32\config\system) and software (WINDOWS\system32\config\software) hives from the mounted image under HKEY_LOCAL_MACHINE, use PE_Sys and PE_Soft.

8. Apply the registry modifications specified in the Microsoft iSCSI software initiator user guide (pages 146-151).

9. Unload the hives and close the registry editor.

10. Unmount the image and commit changes: imagex /unmount /commit C:\winpe_x86\mount

11. Create a bootable ISO: oscdimg -n -bC:\winpe_x86\etfsboot.com c:\winpe_x86\ISO c:\winpe_x86.iso

http://technet.microsoft.com/en-us/library/cc709665%28v=ws.10%29.aspx

WAIK 3.0 Documentation: Step-by-Step: Basic Windows Deployment for IT Professionals.