I believe those addresses are assigned by your router which I assume you are using.
According to a Google search...
"Assuming the subnet mask is 255.255.255.0 then...
You range of total addresses is from 192.168.1.0 - 192.168.1.255 However, the first and last IP addresses cannot be assigned to hosts since they are reserved for internal usage.
The first address, 192.168.1.0, is the subnet address.
The last address, 192.168.1.255, is the broadcast address.
Thus, the host range is from 192.168.1.1 - 192.168.1.254"
If you are worried by "a computer at IP blah blah has tried to invade" in your Inbound Events, that is normal and those are all failed attempts anyway.
Strange that IP that you wanted should already be OK as it is in that range.
I think Technical Support Chat may be able to explain better than anyone here.
Interestingly enough, I tried setting a range from 192.168.1.0 to 192.168.1.254 and it seems to have worked. Maybe something about either the broadcast address is a problem or the pre-defined entry put in by McAfee is somehow not right. Don't know but it appears to be working now.
BTW: I tried chat but every time I tried it it bounced me back to McAfee.com and never loaded. Same with email. So I couldn't email to tell anyone that I couldn't get chat working. Maybe a Firefox problem? Whatever,.. I was totally stuck.
I know this is old but this is still a problem. Why does the rule get created if it does not work. After not being able to see any other computers on the network, I've created the exact same rule(192.168.1.0 - 192.168.1.255,) myself. Leaving the original rule in place and as soon as I do that you can see the other computers on my network. Mcafee should just not create the rule in the first place, its just ridiculous.
The firewall sets the IP range automatically and that shouldn't be altered but you may wish to add others depending on your network use. As this is an old thread as you said and the subject is a bit technical I think Technical Support could explain it better than I can.
I don't have a network so am a bit rusty in that regard.
They are free to phone or use online chat, linked under Useful Links at the top of this page.