Problem with dual boot

In the past, whenever I've installed GNU/Linux to run along side another operating system (specifically I have installed Ubuntu this way in the past), it has been very easy. The installer has had an option "install Ubuntu along side _______".

However, I am currently trying to install Trisquel 6.0 along side another operating system and I'm seeing the other two options only: "Replace ______ with Trisquel" and "Something else". No option to "Install Trisquel along side ______".

I have selected the "Something else" option and tried to install Trisquel along side the other operating system manually, but I have not been successful in this.

I have read these threads:
https://trisquel.info/en/forum/help-dual-boot-install
https://trisquel.info/en/forum/dual-boot-windows-7
and this guide:
https://trisquel.info/de/wiki/install-trisquel-windows-dual-boot

The guide looks exactly as I remember it being for Ubuntu, very easy. However, I am simply not seeing the install along side option. So, I see the note which addresses this possibility.

So as the note directed, I booted Windows 7, defragmented the disk, shrank the volume, and rebooted into the Trisquel installer.

But it still does not have an install alongside option. So I'm wondering, does anyone have any ideas regarding the problem or the solution? Thanks in advance.

Boaz

P.S. I anticipate that some will reply to this post with statements to the effect that "Why would you want to install Trisquel along side Windows 7, just replace Windows 7 completely".

I think it's worth having a discussion on this point.

I completely agree with the idea, and it is what I would do if it were my computer. Indeed, on all computing devices that I own, I run 100% free software (Trisquel on my PC, Replicant on my phone, no proprietary applications on either).

However, I am helping a friend. I hope everyone on this forum understands that it is not within my rights to make unilateral decisions regarding someone else's property.

This friend of mine is running Windows on several computers. In light of http://www.theguardian.com/world/2013/jul/11/microsoft-nsa-collaboration-user-data and other similar stories, and many hours of conversation with me where I argued that the nature of proprietary software makes this sort of thing inevitable, he has agreed in principle that he should migrate away from Windows and proprietary software generally. However, he has anxiety about doing this.

So we've agreed to set up dual boot Windows and Trisquel on one of his computers, then over time to expand to his other computers and eventually wipe out Windows completely.

Believe me, if it were my decision, I would wipe out Windows completely right now on this computer and all his computers. But it is not my choice, and if I can't get dual boot going, he won't let me install Trisquel at all and will simply keep using Windows.

I don't know if the two threads linked above are "locked" in an attempt to censor discussion of this topic.

But I don't think it's helpful in a case such as this to say simply "you shouldn't use proprietary software at all". If he can dual boot, he'll be on a road that will ultimately lead, according to his own plan, to a 100% free computing experience. If not, he'll just use Windows forever.

You might argue that this makes no sense (and I would agree). But this is how he feels. And I suspect many like him feel similarly.

So in conclusion, I'd appreciate if, in addition to criticizing me for my friend's decision, someone writes something about how to solve the problem that this post is about.