If Mcafee says it blocked the probe be happy as checking one's history will find hundreds of such blocks a day. Maybe this block has been instigated by the netguard feature go to Web and email protection and firewall and netgaurd and see if that Ip addy is shown.
you can put that Ip into www.trustedsource.com and says high risk.
To be sure to some scans with the scanners I have in my signature. With getsusp be sure to add your email addy in the preferences and with malwarebytes do not accept the free trial of the premium version use the fully free version.
I recently got a new subscription to my software back in mid May and thus far the software has blocked over 500 attempts from all over the world so the software is in fact doing its job protecting you.
As Peacekeeper already mentioned if you want some additional assurances run some of the scans he mentioned.