I'm seeing unusually long boot times on several Dell 16 Pro PC16250 laptops. Before they're joined to the domain, they boot normally, but after a domain join and reboot, they sit on the Dell SafeBIOS/OEM splash screen for roughly two minutes before reaching the Windows sign-in screen. Disabling the Netlogon service makes the boot time return to normal. I haven't found anything useful in the event logs, and moving the computers to an OU with inheritance blocked didn't change the behavior. All systems are running BIOS version 1.18, and other Dell models in the environment don't have this issue. I've tested both the factory image and a fresh Windows installation, and resetting BIOS settings to factory defaults didn't help. Has anyone encountered this with this Dell model or BIOS version?
4 Answers
I’d avoid relying on the factory Dell image for troubleshooting and reproduce the issue with a clean Microsoft Windows installation plus only the required Dell drivers. Then compare BIOS versions, firmware settings, and driver packages against a Dell model that boots normally. If the clean install still shows the same behavior, that points more strongly toward firmware, network initialization, or a model-specific compatibility issue rather than the image.
It may be worth testing a different BIOS version on one laptop, either by downgrading temporarily or using Dell’s BIOS recovery process. A factory reset only restores the settings; it doesn’t replace the BIOS firmware itself.
The domain connection itself shouldn’t affect the firmware POST screen, but Netlogon can influence the Windows boot process while the OEM splash screen is still being displayed. I’d compare boot behavior with Netlogon disabled and collect detailed Windows boot diagnostics, while also checking DNS, domain controller reachability, and timeout-related system events.
The screen may still be the Windows 11 boot animation over the Dell splash screen rather than the firmware actually hanging. That would explain why the delay changes when Netlogon is disabled.
Since this happens on multiple machines, I’d also test the network and docking setup. Some Dell systems spend extra time during startup negotiating with docks or network adapters. Try an undocked laptop with wired and wireless networking separately, and check whether increasing the BIOS POST delay changes the symptom or only masks it.
I haven’t tried BIOS recovery yet. I did reset the BIOS settings to factory defaults, but that made no difference. Three Dell 16 Pro systems on my desk show the same delay.