You used to have your homepage set to the Google IG page (that's what the /ig part is), which Google discontinued last September. It may have continued to work for a while after this because Google probably didn't get round to removing the page from their server immediately - either that or they possibly temporarily re-directed it to the normal google search page in the hope that people would eventually change their home page.
You need to go into the settings page - on Chrome enter into the web address bar chrome://settings
In the settings you'll see a "On start-up" section and there will be a radio button with the following option selected "Open a specific page or set of pages. Set pages".
The set pages will be blue - click that and in there you should see a line that says
you just need to change that to http://www.google.com
(remove the /ig?hl=en&gl=us bit at the end - the ig bit just tells google to go to ig and the hl bit tells it to use English language (en = English), and the gl but tells it to use Google US, but these aren't necessary as by default google.com is English, US, if you did want a different google for example googe uk just change http://www.google.com
Also once you've done this in the Appearance section of the settings screen there should also be a tick box which has "Show home button" if that's ticked then you might also need to change the URL under that, just click on change next to the URL again and remove the same bit off the end of that url.
I've added an image below with the important bits that need changing, if your using another web browser other than Chrome then you need to follow that browsers procedure for changing the homepage (it should be somewhere in options)