EDIT 18/10/2018
Since people still PM me asking for RobotStudio 4.0 before reach the end of this topic, I think it is time to make some updates on this post.
First, the method described below doesn't work anymore. ABB changed their site, so I don't know any way to download older stuff from there.
Second, the link to download RobotStudio 4.0 is this one here
https://mega.nz/#!JeYnyQSD!-0B…3NyaVDArtpzYWZ053qAMz7vIQ
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ATTENTION! THE METHOD DESCRIBED BELOW DOESN'T WORK ANYMORE.
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In fact, is still possible to download RobotStudio 4.0 from ABB site, but is a little bit tricky.
First, you will need to create an account on https://myportal.abb.com
After you are logged, click on "SolutionsBank", or "Go to old MyABB" (see screenshot abb1.png)
If you clicked on "Go to old MyABB", from there, click on SolutionsBank
You should land on the SolutionsBank page, shown on screenshot abb2.png.
From there, you can find some old ABB software, as RobotStudio 4.0 or QuickTeach.