you have to disable the "secure boot" function and it is best to boot in "legacy" mode, not UEFI in the case of OS7 installation, the Biosu enters the F10 boot menu: F9, POST MENU: ESC. greetings
The discussion revolves around difficulties entering the BIOS on an HP 250 G4 laptop. Users suggest pressing F1 or F10 during the HP logo screen to access the BIOS. Once in the BIOS, the author encounters issues booting from a Windows 7 installation DVD, with suggestions to check the OS boot manager settings, disable USB boot, and ensure the DVD is in the drive. Additionally, it is recommended to disable "secure boot" and switch to "legacy" mode instead of UEFI for successful installation. Summary generated by the language model.