According to Deployment Research, we can specify screen resolution in WinPE using an answer file.

Wpeinit is rejecting resolution settings in an unattend file. Any idea what has changed that is causing this issue?

Startnet.cmd:

wpeinit -unattend:unattend.xml

Unattend.xml

<?xml version="1.0" encoding="utf-8"?>
<unattend xmlns="urn:schemas-microsoft-com:unattend">
        <settings pass="windowsPE">
                <component name="Microsoft-Windows-Setup" processorArchitecture="amd64" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                        						            <Display>
				<HorizontalResolution>1024</HorizontalResolution>
				<VerticalResolution>768</VerticalResolution>
				<ColorDepth>32</ColorDepth>
				<RefreshRate>60</RefreshRate>
			</Display>
                </component>
</settings>
</unattend>

Wpeinit.log:

2013-04-05 04:34:10.067, Info      WPEINIT is processing the unattend file [x:\windows\system32\unattend.xml]
2013-04-05 04:34:10.083, Info      ==== Initializing Display Settings ====
2013-04-05 04:34:10.083, Info      Setting display resolution 1024x768x32@60: 0xfffffffe
2013-04-05 04:34:10.083, Warning   Setting the display resolution failed; this error is being ignored
2013-04-05 04:34:10.083, Info      STATUS: SUCCESS (0x00000001)

Any ideas?

I am using WinPE 4 x64.

WinPE in UEFI mode is using Graphic Output Protocol (GOP) mode to determine screen resolution. So far no "supported" method of changing the resolution has been mentioned. I didn't get much time to research it yet, been putting out other fires.

http://social.technet.microsoft.com/Forums/en-US/w8itproinstall/thread/eb9c59df-7f93-487e-ae59-c5954da5866f/