In a nutshell McAfee doesn't alter IE at all, however it does use it. The consumer products removal tool is called MCPR and is linked under Useful Links at the top of this page. Run it and reboot and repeat if removal is incomplete.
Windows 7 SP1 ?
The network connection should be restorable by right-clicking the taskbar icon network icon and selecting Diagnose and Repair.
Or you can get it to it through the Control Panel.
I just ran into the same problem under Windows 8, IE 10. The uninstaller did not crash to my knowledge, but the exact type of pages you describe stopped functioning. I couldn't even get the download buttons for chrome or firefox to work. IE remains crippled even after a windows features disable and re-enable. We have not tried MCPR.
As the above poster never reported back we don't know how it turned out. If there's a problem uninstall in the normal way, run the MCPR cleanup tool, reboot and then reinstall if you want the software. The above behaviour is not normal, believe me and is probably due to a corrupted installation.
Technical Support is available free of charge by phone or online chat and linked, along with the removal tool, under Useful Links at the top of this page.
Okay, running MCPR fixed Internet Explorer. Why does the normal Windows Add/Remove Programs not properly remove the program? The fact that this tool is required at all should be fixed or made obvious during the normal uninstall process. Sticking with Windows Defender.
I agree with you and normally it shouldn't be required, However we've found that installations get corrupted for so many reasons, malware, use of registry cleaners, the list goes on, that the tool was developed to pick up stray registry keys.