There's some good information in that link.
The very first thing to do is check your startups for undesirables that could be responsible:
Now go to Start/run, and type Msconfig. On the Startup tab, look to see if you can find one or more of the following entries:
SWPortal, SWCaller, Sp.dll, winn32.html, runme.hta, reg.hta, adshow.exe , OPQfile, and/or MSKernel32 (Win32.hta).
If you should find one or more of these, uncheck them.
Also anything that has 'regedit.exe/s' in its path.
Now click OK, close Msconfig, and reboot.
If your undesired site is 'GoHip', you need to download and run
GoHip Remove.exe
Good luck,