You can only turn "SecureBoot isn't configured correctly" off if you turn SecureBoot on...

WinBeta - How to remove the 'SecureBoot isn't configured correctly' watermark on Windows 8.1

For those who were one of the lucky ones to successfully download and install the Windows 8.1 update while numerous users are experiencing difficulties, you are likely to be enjoying all the new consumer requested features that the update brings to Windows 8. However, there is one annoyance that has popped up regarding Secure Boot, leaving an annoying watermark on the desktop.

Some Windows 8.1 users are reporting that they have a watermark stating "SecureBoot isn't configured correctly." Here is why it appears and how you can fix it, for now at least.

...

Apparently the only solution to disable the watermark is to actually enable Secure Boot in the BIOS. At the moment, there seems to be no workaround to remove the watermark if the Secure Boot option is disabled in the BIOS.

...

I've got a couple machines with this whiny watermark and this post does the best I've seen in explaining it and how to, such as it is, resolve it. I'm going to keep my eyes open for another option as I find that watermark annoying and I don't want to enable SecureBoot (or deal with any driver issues that might result in turning it on)...