Why can’t my computer run Windows 11?
QI’m attempting to get my PC to update to Windows 11, but when I try I get a message that my computer must support Secure Boot. However, I’ve looked in the BIOS and, as far as I can see, it does – it says enabled! I’ve tried disabling it then enabling it, and I’ve reset numerous other settings to default.
However, Microsoft’s PC Health Check app (www.snipca.com/41756) still says it isn’t supported. I’ve seen plenty of advice on TPM but very little on Secure Boot. I don’t know where to turn to next. Ian Trotter
AThis is probably because your computer’s boot drive was set up using the traditional master-boot record (MBR) system (see screenshot above right), but starting up with Secure Boot needs a drive prepared with a globally unique partition table (GPT).
For reasons we’re about to explain, this ideally should be done before installing any operating system.
The good news is that you can convert an existing MBR drive to GPT. The bad news is that doing so carries some risk, because if you make a mistake or something goes wrong, you can kiss goodbye to any data on the drive. If you’re okay with that then it’s straightforward, though do back up!
First click Start followed by Settings, then ‘Update & Security’, and then Recovery followed by Restart. Next, click Troubleshoot followed by ‘Advanced options’, and then click Command Prompt. Note that you might at this point need to log into Windows 10.
The required command is mbr2gpt /convert /allowfullos, which you’ll also find on our Pastebin page at www.snipca.com/41757.
So, type that into the Command Prompt window, or copy and paste it from Pastebin, and then press Enter. Now just wait while the task completes.