Thank you for your replies. Just wondering do I need to use these if I do a full erase and re-install?
And here is a picture of the #page1 Yahoo icon and a bit more information
At the start what made me realise there was something wrong is a Google search was re-directed to a Yahoo search. So after I erased and re-installed and saw this second Yahoo icon in Favorites it didn't seem right
When I open Yahoo from the #page1 icon it starts off being "au.tv.yahoo.com" then changes to "https://au.yahoo.com/err..." and also in the address is "Aussies complain nbn is slow..." It also has a message "Hmmm...the page that you're looking for isn't here, Try searching above" When I open Yahoo on another computer everything is just the same but it does not have this message
Another thing, when I try to install from USB installer, there is a message saying it is damaged. I Googled and found I have to set the clock in Terminal to 2019, then it will install
Just tonight I did another full erase and installed High Sierra via Internet Recovery and the #page1 Yahoo icon is still there and still the same. Usually when I do an Internet Recovery it installs Lion OSX which is what it shipped with. Have Apple dropped that now and only offer High Sierra? (This computer is too old to install Mojave)
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And here is the message "'Hmm...the page that you're looking for..."
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