Eileen
I have no insight into OCF server set up and could not log in as a returning customer on the OCF store when I joined (luckily I have several email addresses so just registered) Logging into any password site with a new computer can be tricky since your new computer does not have the magic "cookie".  I suggest you go to the forum page, go to registered users, fill out the user name box and your password then hit enter.  I always get confused because some sites just want charm2017 and others want 
[email protected] (I left xxx so spiders don't harvest my email and spam me to death).  Good luck 
I didn't know you could even buy computers anymore with XP.  I don't think it is your McAfee as I actually activated my 30 day free trial just so I could formally register and review OCF as a SAFE site not to be blocked.  I was the first reviewer on the McAfee web site for OCF.  I will just let it lapse as I find that my own personally configured router on top of my cable company's modem and Windows Defender all together work just as well as expensive security suites
I share your frustration and we miss your posts.  Get on line soon