Frustrating problem on my dell optiplex . Number lock is set in bios to be on ,but every time I power off and back on the number lock has been overwritten and switched off . This does not happen on a restart but only at power off . I have used the windows 10 forum and searched at length for a fix but no solutions work . The most common suggested fix is in the registry changing the relevant entry to 2 but does not work . I am using a Logitech wireless keyboard and mouse set . Must be something that windows 10 does at startup but well beyound my capabilities . any help will be appreciated .