I recently let my Windows 10 Insider Preview build expire. After October 15, 2015 it would not boot. Winload produced a blue-screen error about expired components. After much research and work I figured out how to get it back to good standing, despite Microsoft's attempts to block it.
First, the date on the computer must be set back to a date before the expiration so that Windows will think it is not yet expired. However Microsoft tries to prevent users from doing this by storing the expiry status on the hard disk. To overcome this, the file C:\Windows\bootstat.dat must be deleted. But because the computer can't be booted, not even for recovery, you can't get to point where you can delete the file.
The solution is to boot the computer from a non-Windows 10 install/recovery DVD or USB drive.
Boot from a Recovery CD
These are three options you can use:
- A Windows 8.1 Install DVD which has a recovery mode that would allow you to run a Command Prompt and delete the file from the command line.
- A Linux Install DVD with a recovery mode, like Fedora Linux's install media. To use this method you'd have to be proficient with Linux because you'd have to use the command line to mount the Windows C: drive and delete the file.
- A specialized boot disk like Hiren's BootCD and use Windows Explorer to delete the file.
Number 3 might be the easiest but you'll need another computer to download the CD image and burn it to a CD.
Whichever boot option you use, you must delete C:\Windows\bootstat.dat.
Set the Date Back
Next, you'll need to reboot the computer. During the reboot the you'll need to enter the BIOS setup to set the date back to before the expiry. The exact process for doing this will depend on your computer type.
Turn Off Network Time Synchronization
If you're system was configured to synchronize the date and time with a network server, you'll have to turn that off and then repeat the above steps because Windows will figure out that the date is set back when you boot it and reset it to the current date and again create C:\Windows\bootstat.dat.
Disable Network Card
For me this also required disabling my wireless network card because if you boot with it on, Windows immediately discovers what the true date is an refuses to load.
I disabled my wireless network card by unscrewing the antennas. If you don't have antennas you will probably have to remove it from the computer. If its built-in, then you may be able to disable it in the BIOS setup screen.
Update to Latest Preview Build
When the computer successfully boots with the date set back and network time sync turned off, you can update to the latest build. If you disabled your network card to get to this point, you'll have to re-enable it so that Windows Update will work.
If you're in the insider program, Windows Update should already be set to update to the latest build. Use Windows Update to make sure it is configured to download and install builds when they're available. It should automatically find and install the most recent build, which could be newer than the final public Windows 10 release as it was in my case.
An update to the latest build will require a reboot. At that point it is safe to let Windows discover the true date and time, which it most likely will do automatically as it did in my case.
Activation - CRITICAL
If, during the update, Windows asks you for an Activation Key, you should not enter one. If you do, it will assume you need to enter a key and will forever keep trying to get you to enter one.
You should instead click "Don't have a key" or "Skip" to get past the key entry screen. Windows will thereafter automatically figure out that you're in the Insider program and eventually retrieve your activation information from the network.