A fresh install of Debian wheezy doesn't detect WinXp.

The computer is an amd64 and Debian is at /dev/sda and xp is at /dev/sdb1

The computer boots into xp when I unplug the data cable to the /dev/sda drive.

I have tried to follow some 5 or 8 different [solved] threads with no succsess.

And slightly off topic. How do I get some useful colour settings to emacs? Now some colour schemes can be a variable white on white. Marking text for copy/paste is unvisible.

That is nice.

That is about all anyone can say at this point.

What did you do to try and correct the problem?

How on earth did you get anything to have an address of /dev/sda except the mbr?

Knowing my expert ability when it comes to typos I assume that Debians / partition is sda1. But this must be confirmed.

To make this as easy as possible go to;
http://bootinfoscript.sourceforge.net/

Download and follow the directions for running the script from your Debian install making sure that the XP drive is cleanly connected.

Post the entire output of that script.

You should remove the emacs question from your post and start a clean thread for that question. One or both of your questions my be of interest of people that make use of the forum search function. They will find nothing about emacs on this thread by that method.

You will also have a more coherent thread if only one issue is considered.

1 members found this post helpful.

You can try manually loading Windows from the GRUB Boot Loader command line. And if it works make a menuentry for Windows.

OK... First on an empty hard drive a couple of years ago, in a newly assemled computer Widows Xp got installed.

Then another hard drive got installed with Debian. And it... worked. It was Lenny.

Then it Debian got upgraded to Squeeze. Ant it... worked. Dual boot worked with no effort.

The computer XP installed for Band-In-A-Box and nothing else.

Since I started with Linux (Redhat Picasso spring 1996 edition) Dual booting Windows simply used to work with no bigger effort put into it. lilo and later grub simply magicly used to detect DOS.

Eventually Lenny got severely outdated so Debian had to be upgraded. And to get Ardour 3 for hard disk recordings it had to be Wheezy.

The install procedure was exactly as it used to be. But this time WINDOWS I NOT DETECTED.

The computer with XP-drive plugged in to SATA 2 jack boot windows so i guess it is there and mbr and all that is as it should.

The computer with Debian-drive plugged in to SATA 1 jack boots showing the grub meny with 2 different linux kernel to choose from.

The computer with Debian-drive plugged in to SATA 1 and XP-drive plugged in to SATA 2 jack... The computer boots to the grub menu showing the two Linux kernel and nothing else.

I have tried:
(after the Debian upgrade process)
os-prober
update-grub
install-grub /dev/sda (don't remember the exact options)

Some versions of creating files in /etc/grub.d
(don't remember as this is written on anothercomputer)

one said one should create a file /etc/grub.d/11_wondows
another said one should put some lines in /etc/grub.d/40_custom
(note that 40 might be wrong number don't remember exactly)
And I tried to put some lines in another /etc/grub.d/XX_somename file.

And I tried to start xp manually from the grub boot menu.

The problem is not /dev/sda. It contains a couple of ext4 partitions and a swap partition. It is just mentioned to inform where Linux is. Linux works. Linux boots.

The problem is, that what is on the /dev/sdb1 partition is not detected by grub.

And for clairity. /dev/sda is mentioned to inform what hard drive was unplugged. The entire drive with all partitions and mbr and everyting. Can, lets say, only /dev/sda2 get unplugged by pull the cable?

I guess you followed these steps after plugging in the second HDD? (By the way, the last command should have been grub-install /dev/sda).

In any case, run the bootinfo script with both HDDs plugged in as widget suggested and post back the RESULTS file here. It can show where the problem is.

Run the boot info script from Debian making sure there is a clean connection for the sdb drive.

You have unplugged and replugged sda a couple times. That contact should be clean.

There is, however, the chance that the contacts are not that clean for sdb. This could cause some communications problems with Debian on sda.

Running os-prober is not needed. Running "update-grub" regenerates the /boot/grub/grub.cfg file which generates your grub screen menu. This is done using the contents of /etc/default/grub and the scripts contained in /etc/grub.d. One of those scripts runs os-prober.
/etc/grub.d/30_os-prober

It is the results from that run of os-prober that is used to generate grub.cfg.

The results of the boot info script will tell us if all those scripts are healthy.