I suspect that it's because Windows 8.1 is set at its default startup type - hybrid aka fast startup.
Try disabling this as per this tutorial: Fast Startup - Turn On or Off in Windows 8
Disabling it wont really make a startup difference normally as all it really does is ensure the computer turns totally off rather than hibernates at shutdown.
From a computer user with experience's point of view that's a good thing as Windows needs to be shut down at regular intervals to ensure updates take properly and for self-checking reasons.
BTW there are some other handy shortcuts at the bottom of that tutorial and many more listed in the main index.
I've disabled the fast startup but this didn't affect the startup time of Mcafee, which was still delayed.
I will try one of the registry options to reduce the startup delay and report back.
Cheers for the tips so far.
I have now tried reducing the startup delay time, as suggested at: Startup Delay Time - Reduce in Windows 8, but this has no impact.
Is there a way to disable real time scanning so it doesn't even attempt to start up? I have disabled but it always try to start anyway!
Alternatively as there aren't any other replies can someone from support get in touch?
I wouldn't try switching real-time scanning off as that is your protection.
As PK has suggested I would open a case with Technical Support, it's free by phone or online chat and if at first they don't succeed, ask them to escalate it.
BTW I often find it beneficial to disable things from the Startup if not needed, but only do that to non-security things.
Click the Windows key + R
In Run type msconfig and click Enter. OK the prompts.
Go to the Startup tab and disable unnecessary items there.
Don;t disable McAfee or any Windows process though.
Also check for competing security software.
Mcafee is one of the few things enabled in Startup. FYI, I'm on Windows 8.1 and the startup settings are in Task Manager.
I have disabled the real time scanning as I don't want it running. If I disable somehting, it shouldn't try and start and the realise it's disabled, as is the case in hand.
It tries to restart it as the program assumes RTS turned off is caused by malware thus the restart.
You also said RTS off did not help so why have you got it disabled, ok your choice but not the safest? I would try support and escalate the call if the support person cannot help.
I also wonder if the 14 version improves things I will ask a tech his thoughts as well.