uefi 42.1

do I have to use uefi/have it enabled to install 42.1 ??

I don’t fully understand the question. That is to say, I’m not sure what you are looking for.

The installer can either boot with UEFI, or it can boot with legacy BIOS booting. Use whichever your computer supports.

If your computer supports UEFI, it is generally best to boot that way. However, if you already have Windows installed for legacy booting, then you should boot the installer in legacy BIOS mode. That’s because legacy booting and UEFI booting do not mix well.

thank you for reply and sorry to confuse, my install failed,and I presumed it was something to do with my bios/uefi settings,but apparently for no known reason it installed on the third attempt.
however all seams well apart from a glitch…when I close my browser I get logged out of the OS and cannot log back in I have to restart my pc !!!
any ideas or should I start a new thread ??

Start a new thread. Indicate which desktop you are using, and which browser.