Black screen and red box

[Kelly1984]

Can anyone help. 
when swiping on I get a black screen with red box saying “ secure boot violation , invalid  signature detected” 

[Grzwacz]

Hi,

Have you installed new hardware?

An invalid Secure Boot signature may be caused by malware, or BIOS corruption, or new hardware.

Tough to conclude the cause of your issue.

You can turn off Secure Boot using instructions at this (Link). Doing this will allow malware to run if you are infected.

Regards