Oops! I have done a bad thing and forgot what install method and what particular .iso I was installing from.

A few months ago I had to get a new machine and tried to set up my dual boot system again. I have windows 7 64-bit on a Thinkpad p50. I began the installation process (I stopped halfway because during restart, my Win 7 was set to a 0 sec pause and I could not select the Debian in Windows Boot manager in order to continue-- and I didn't know how to change the pause time and didn't have time to find out during the school year) and there is currently a Debian entry on my windows boot manager. It says something like, "Debian Linux (resume installation process)."

The bad part is I have no idea whether I was going the netinst route, or if I had made a bootable CD or USB with the full install-- and beyond that, I'm not even sure which .iso file I was using, as I have several of them on my external drives where I keep these things. I'm not even sure if I partitioned space for the Debian yet, but the windows partitioning tool seems to indicate I did not partition it, I think (there's 100 mb partition that I don't know what it is).

Is there some way to find out this information (install method, .iso used) so I can continue where I left off with the install, or do I need to clear some stuff out and start anew? I have a little bit of knowledge in Debian and Windows but am not much more than a newbie. Help/advice appreciated!

Personally I would just use the first CD I found and clobber the partial installation. Be very sure you know which partition it is on, and when the partitioning menu comes up just choose that partition as if it was empty.

You should ideally know the partition information ahead of time. I don't know how to find it in Windows (haven't used it in a decade), but it can't be too hard. fdisk -l might even work in the command prompt.

If there's really nothing partitioned yet, then there's nothing saved, and thus no point in resuming an installation. But yeah, the first step is to print your partition table somehow, like fdisk -l, for example mine is:

/dev/sda1 2048 6143 4096 2M BIOS boot
/dev/sda2 6144 268287 262144 128M Microsoft basic data
/dev/sda3 268288 10508287 10240000 4.9G Linux swap
/dev/sda4 10508288 92311551 81803264 39G Linux filesystem
/dev/sda5 133388288 234440703 101052416 48.2G Microsoft basic data
/dev/sda6 92311552 133388287 41076736 19.6G Microsoft basic data

And those are all linux, it just labels them incorrectly pretty often. It will find those during partitioning, too, and you can look at them. As long as you don't apply your changes, you can bail on the installation again without hurting anything. For a minimal installation you'll want at least 8 gigs probably, and a separate partition with a gig or two for swap (I'm pretty sure I've never actually used my swap, but all I do is code and play Dwarf Fortress).

If there's no free space, you'll have to either make windows give some up, from within windows, which I don't know anything about, or use one of your external hard drives. You'd have to make it bootable (that is, install grub) and then you'd basically use the BIOS to switch operating systems. I've used a USB hard drive for lubuntu before and the performance didn't take too big of a hit, depending on what you want to use it for. Of course, repartitioning the external drive will destroy the existing file system unless you use some fancy tool, so you'll most likely lose any data you have on it. You could attempt resizing the file system with a live CD that has partitioning tools on it, but I've never tried this and wouldn't expect it to work.

You would use bcdedit to make changes on your windows bootloader. To change the timeout, boot windows 7 and get command prompt with: Start, All Programs, Accesories, right click command prompt and select run as administrator. Edit BCD with the command above changing the 30 to whatever you want.

To Verity Nezkrotny,

+1 (I agree with the above post)
I suggest you reading https://www.debian.org/releases/stable/amd64/ , especially https://www.debian.org/releases/stab...4/ch03.html.en and https://www.debian.org/releases/stab...h03s05.html.en
and for which debian iso file is necessary,
https://www.debian.org/CD/faq/index.en.html#which-cd

+1
As for partitioning, how about reading http://www.howtogeek.com/101862/how-...ther-software/ ?

I suggest you making backups of Master boot record, and partition boot records of existing Windows partitions, and EFI System partition (if there is), after preparation of partitions necessary for debian installation.
In linux, you can make backups as follows with root privilege:
I assume sector size is 512 bytes.
The above X, Y, /PATH/TO/SAFE_PLACE should be replaced with proper letters.
/dev/sdX should be the internal media, such as the internal HDD.
/dev/sdXY should be Windows partition.
/PATH/TO/SAFE_PLACE should be a safe place which will not be damaged by future debian installation.
You may know the proper values for X and Y, by
If there is a EFI System Partition,
/dev/sdWX should be the EFI System Partition.


If you want to boot live debian, you may find the iso file at https://www.debian.org/CD/live/index.en.html
But be careful. There was a report that live debian could not install grub2 correctly, which made a problem.


+1
I wonder if you executed (double-clicked) setup.exe in the iso file. I wonder if it adds boot entry for starting installer of debian, into windows boot entries.