and welcome to BleepingComputer.
I think that the Hijack and the SpySheriff malware all fall under the same infection. What I would suggest you do is that you firstly read the self help instructions which can be found here
. Please use those instructions as a guide to removing SpySheriff from your computer. If you are not happy doing it by yourself and would like 1 to 1 help, or cannot remove the program using the self-help guide please reply and we can consider the options possible. Then, after you have completed that, let me know in this thread whether or not the Hijack has stopped or whether your McAfee is flagging the PUP virus anymore. It could be that you have more than one infection and, as I said above, we may need you to post a Hijack-this log or complete a few other scans to remove it.
Best of luck