windows boot problem after installing ubuntu

[Marcel_V]

Hello all,

I've recently decided to install Ubuntu on my laptop alongside Windows Vista using an installation cd. I've never encountered any major problems before, but after installing Ubuntu 10.04, Windows won't boot normally. After I select Windows from the grub menu, the Windows loading screen appears. Sometimes it loads completely, but other times it suddenly reboots my computer. I've searched the net for a solution, but I can't find anyone with the same problem, so I thought I'd ask here. Any help will be greatly appreciated.

Kind regards,

Marcel

[Rubi1200]

Hi and welcome to the forums :)

Use a LiveCD or LiveUSB to boot the computer, choosing the option to try without any changes.

1. Download the boot info script. There is a link in my signature.
2. Move the boot info script to the desktop.
3. Open a terminal and run the command

sudo bash ~/Desktop/boot_info_script*.sh
This will create a RESULTS.txt file on the desktop. Paste the entire contents of that file back here. Once pasted highlight all text and click the # sign on the toolbar to place code tags around the text.

[Marcel_V]

Thanks for the reply. Here are the results:


Boot Info Script 0.55 dated February 15th, 2010

============================= Boot Info Summary: ==============================

=> Grub 2 is installed in the MBR of /dev/sda and looks on the same drive in
partition #4 for (,msdos4)/boot/grub.

sda1: __________________________________________________ _______________________

File system: ntfs
Boot sector type: Windows Vista/7
Boot sector info: No errors found in the Boot Parameter Block.
Operating System: Windows Vista
Boot files/dirs: /bootmgr /boot/bcd

sda2: __________________________________________________ _______________________

File system: ntfs
Boot sector type: Windows Vista/7
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files/dirs: /bootmgr

sda3: __________________________________________________ _______________________

File system: Extended Partition
Boot sector type: -
Boot sector info:

sda5: __________________________________________________ _______________________

File system: swap
Boot sector type: -
Boot sector info:

sda4: __________________________________________________ _______________________

File system: ext4
Boot sector type: -
Boot sector info:
Operating System: Ubuntu 10.10
Boot files/dirs: /boot/grub/grub.cfg /etc/fstab /boot/grub/core.img

=========================== Drive/Partition Info: =============================

Drive: sda ___________________ __________________________________________________ ___

Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes

Partition Boot Start End Size Id System

/dev/sda1 * 63 229,702,341 229,702,279 7 HPFS/NTFS
/dev/sda2 606,418,944 625,135,615 18,716,672 7 HPFS/NTFS
/dev/sda3 229,703,678 237,514,751 7,811,074 5 Extended
/dev/sda5 229,703,680 237,514,751 7,811,072 82 Linux swap / Solaris
/dev/sda4 237,514,752 606,416,895 368,902,144 83 Linux


blkid -c /dev/null: __________________________________________________ __________

Device UUID TYPE LABEL

/dev/sda1 94CC802BCC800A26 ntfs
/dev/sda2 04CA8347CA833448 ntfs PRESARIO_RP
/dev/sda3: PTTYPE="dos"
/dev/sda4 ce42f8c9-20af-4641-a4f9-143814ea2f6d ext4
/dev/sda5 86793bfd-a5ce-41e2-8e53-9672c7897288 swap
/dev/sda: PTTYPE="dos"
error: /dev/sdb: No medium found

============================ "mount | grep ^/dev output: ===========================

Device Mount_Point Type Options

/dev/sda4 / ext4 (rw,errors=remount-ro,commit=0)
/dev/sr0 /media/Ubuntu 10.10 i386 iso9660 (ro,nosuid,nodev,uhelper=udisks,uid=1000,gid=1000, iocharset=utf8,mode=0400,dmode=0500)


=========================== sda4/boot/grub/grub.cfg: ===========================

#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
set have_grubenv=true
load_env
fi
set default="0"
if [ "${prev_saved_entry}" ]; then
set saved_entry="${prev_saved_entry}"
save_env saved_entry
set prev_saved_entry=
save_env prev_saved_entry
set boot_once=true
fi

function savedefault {
if [ -z "${boot_once}" ]; then
saved_entry="${chosen}"
save_env saved_entry
fi
}

function recordfail {
set recordfail=1
if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi
}

function load_video {
insmod vbe
insmod vga
}

insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
if loadfont /usr/share/grub/unicode.pf2 ; then
set gfxmode=640x480
load_video
insmod gfxterm
fi
terminal_output gfxterm
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
set locale_dir=($root)/boot/grub/locale
set lang=en
insmod gettext
if [ "${recordfail}" = 1 ]; then
set timeout=-1
else
set timeout=10
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Ubuntu, with Linux 2.6.35-24-generic' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux /boot/vmlinuz-2.6.35-24-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro quiet splash
initrd /boot/initrd.img-2.6.35-24-generic
}
menuentry 'Ubuntu, with Linux 2.6.35-24-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
echo 'Loading Linux 2.6.35-24-generic ...'
linux /boot/vmlinuz-2.6.35-24-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.35-24-generic
}
menuentry 'Ubuntu, with Linux 2.6.35-22-generic' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux /boot/vmlinuz-2.6.35-22-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro quiet splash
initrd /boot/initrd.img-2.6.35-22-generic
}
menuentry 'Ubuntu, with Linux 2.6.35-22-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
echo 'Loading Linux 2.6.35-22-generic ...'
linux /boot/vmlinuz-2.6.35-22-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.35-22-generic
}
### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###
### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry "Memory test (memtest86+)" {
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux16 /boot/memtest86+.bin
}
menuentry "Memory test (memtest86+, serial console 115200)" {
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux16 /boot/memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###

### BEGIN /etc/grub.d/30_os-prober ###
menuentry "Windows Vista (loader) (on /dev/sda1)" {
insmod part_msdos
insmod ntfs
set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set 94cc802bcc800a26
chainloader +1
}
menuentry "Windows Vista (loader) (on /dev/sda2)" {
insmod part_msdos
insmod ntfs
set root='(hd0,msdos2)'
search --no-floppy --fs-uuid --set 04ca8347ca833448
chainloader +1
}
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries. Simply type the
# menu entries you want to add after this comment. Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f $prefix/custom.cfg ]; then
source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###

=============================== sda4/etc/fstab: ===============================

# /etc/fstab: static file system information.
#
# Use 'blkid -o value -s UUID' to print the universally unique identifier
# for a device; this may be used with UUID= as a more robust way to name
# devices that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
# / was on /dev/sda4 during installation
UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=86793bfd-a5ce-41e2-8e53-9672c7897288 none swap sw 0 0

=================== sda4: Location of files loaded by Grub: ===================


284.9GB: boot/grub/core.img
199.1GB: boot/grub/grub.cfg
122.4GB: boot/initrd.img-2.6.35-22-generic
122.5GB: boot/initrd.img-2.6.35-24-generic
284.9GB: boot/vmlinuz-2.6.35-22-generic
284.9GB: boot/vmlinuz-2.6.35-24-generic
122.5GB: initrd.img
122.4GB: initrd.img.old
284.9GB: vmlinuz
284.9GB: vmlinuz.old
=======Devices which don't seem to have a corresponding hard drive==============

sdb

[kansasnoob]

I'm a bit rusty at this as I've had little time to play in the past several months so you may be well served to wait for a second opinion on this :)

But I believe you're missing some Win boot files:


sda1: __________________________________________________ _______________________

File system: ntfs
Boot sector type: Windows Vista/7
Boot sector info: No errors found in the Boot Parameter Block.
Operating System: Windows Vista
Boot files/dirs: /bootmgr /boot/bcd

I believe that should be:


Boot files/dirs: /bootmgr /Boot/BCD /Windows/System32/winload.exe

Do you have a Windows recovery disc? If not you can get one here:

http://neosmart.net/blog/2008/windows-vista-recovery-disc-download/

Meierfra's instructions here were for Win7 but the procedure is similar:

http://ubuntuforums.org/showpost.php?p=8929988&postcount=357

You may have to recover grub2 after completing that:

https://help.ubuntu.com/community/Grub2#Reinstalling%20GRUB%202

[kansasnoob]

I'm bumping this because I'm curious if I was right or wrong.

[Marcel_V]

I tried repairing windows, updating the grub menu and test it with a couple of reboots, that didn't do much good. Then I looked for the winload.exe file and it turns out there are two Windows/System32 directories: one in the Windows file system containing the winload.exe file and one at the root of the harddrive with completely different contents (and no winload.exe).

So nothing has changed so far. Ubuntu works fine and Windows still nags about an interrupted startup.

[kansasnoob]

I'd bet either presence1960 or oldfred could figure this out in very short order so be patient and try to keep bumping it from time to time.

[Rubi1200]

I suggest you try the commands here:
http://support.microsoft.com/kb/927392

From what I have read on other forums, you may have to run this 3 times to get it to work.

[Marcel_V]

Well, this is just a great opportunity to get to know Ubuntu. Thanks for your efforts.

[oldfred]

The /Windows/System32/winload file is normally in the main windows system partition. That usually cannot be recovered and is part of the main system(s) folders. The /boot/BCD and /bootmgr files are the one's that the windows repair CD will fix or add. Windows will also fix the windows partition boot sector and the MBR.

IF the /windows/system & windows/system32 folders & files are there then it should be repairable. But I do not know why script would not see the winload file. Did the folder get accidentally moved. I have clicked & dragged an essential folder when I only meant to click.

If you somehow have two windows/system32 folders that would confuse windows. We have seen where Ubuntu/grub creates a /boot where a /Boot exists and that prevents booting.

[Marcel_V]

I suggest you try the commands here:
http://support.microsoft.com/kb/927392

From what I have read on other forums, you may have to run this 3 times to get it to work.

Thanks for the info. I tried it, but unfortunately it didn't work. I've also tried asking some of my friends and they said it's a Windows problem, but even after reinstalling Windows and Ubuntu the problem persists.

[Rubi1200]

Do me a favor and run the boot info script as before and post it here so we can see what, if anything, has changed.

A couple of questions:

do you have any software like Adobe or McAfee or some kind of backup/partitioning software for Windows?

was the drive ever part of a RAID setup to your knowledge?

[Marcel_V]

To answer your first question: I have a Windows system recovery partion (/dev/sda2) that was already there when I bought the laptop. There's no partitioning software on Windows that I know of, so I used Ubuntu's disk utility to take a look at the partitions.

Second: I have no idea what RAID is. I've looked it up, but I still don't understand.

And here are the results from the script:


Boot Info Script 0.55 dated February 15th, 2010

============================= Boot Info Summary: ==============================

=> Grub 2 is installed in the MBR of /dev/sda and looks on the same drive in
partition #4 for (,msdos4)/boot/grub.

sda1: __________________________________________________ _______________________

File system: ntfs
Boot sector type: Windows Vista/7
Boot sector info: No errors found in the Boot Parameter Block.
Operating System: Windows Vista
Boot files/dirs: /bootmgr /boot/BCD

sda2: __________________________________________________ _______________________

File system: ntfs
Boot sector type: Windows Vista/7
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files/dirs: /bootmgr

sda3: __________________________________________________ _______________________

File system: Extended Partition
Boot sector type: -
Boot sector info:

sda5: __________________________________________________ _______________________

File system: swap
Boot sector type: -
Boot sector info:

sda4: __________________________________________________ _______________________

File system: ext4
Boot sector type: -
Boot sector info:
Operating System: Ubuntu 10.10
Boot files/dirs: /boot/grub/grub.cfg /etc/fstab /boot/grub/core.img

=========================== Drive/Partition Info: =============================

Drive: sda ___________________ __________________________________________________ ___

Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes

Partition Boot Start End Size Id System

/dev/sda1 * 63 229,702,341 229,702,279 7 HPFS/NTFS
/dev/sda2 606,418,944 625,135,615 18,716,672 7 HPFS/NTFS
/dev/sda3 229,703,678 237,514,751 7,811,074 5 Extended
/dev/sda5 229,703,680 237,514,751 7,811,072 82 Linux swap / Solaris
/dev/sda4 237,514,752 606,416,895 368,902,144 83 Linux


blkid -c /dev/null: __________________________________________________ __________

Device UUID TYPE LABEL

/dev/sda1 94CC802BCC800A26 ntfs
/dev/sda2 04CA8347CA833448 ntfs PRESARIO_RP
/dev/sda3: PTTYPE="dos"
/dev/sda4 ce42f8c9-20af-4641-a4f9-143814ea2f6d ext4
/dev/sda5 86793bfd-a5ce-41e2-8e53-9672c7897288 swap
/dev/sda: PTTYPE="dos"
error: /dev/sdb: No medium found

============================ "mount | grep ^/dev output: ===========================

Device Mount_Point Type Options

/dev/sda4 / ext4 (rw,errors=remount-ro,commit=0)


=========================== sda4/boot/grub/grub.cfg: ===========================

#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
set have_grubenv=true
load_env
fi
set default="0"
if [ "${prev_saved_entry}" ]; then
set saved_entry="${prev_saved_entry}"
save_env saved_entry
set prev_saved_entry=
save_env prev_saved_entry
set boot_once=true
fi

function savedefault {
if [ -z "${boot_once}" ]; then
saved_entry="${chosen}"
save_env saved_entry
fi
}

function recordfail {
set recordfail=1
if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi
}

function load_video {
insmod vbe
insmod vga
}

insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
if loadfont /usr/share/grub/unicode.pf2 ; then
set gfxmode=640x480
load_video
insmod gfxterm
fi
terminal_output gfxterm
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
set locale_dir=($root)/boot/grub/locale
set lang=en
insmod gettext
if [ "${recordfail}" = 1 ]; then
set timeout=-1
else
set timeout=10
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Ubuntu, with Linux 2.6.35-24-generic' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux /boot/vmlinuz-2.6.35-24-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro quiet splash
initrd /boot/initrd.img-2.6.35-24-generic
}
menuentry 'Ubuntu, with Linux 2.6.35-24-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
echo 'Loading Linux 2.6.35-24-generic ...'
linux /boot/vmlinuz-2.6.35-24-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.35-24-generic
}
menuentry 'Ubuntu, with Linux 2.6.35-22-generic' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux /boot/vmlinuz-2.6.35-22-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro quiet splash
initrd /boot/initrd.img-2.6.35-22-generic
}
menuentry 'Ubuntu, with Linux 2.6.35-22-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
echo 'Loading Linux 2.6.35-22-generic ...'
linux /boot/vmlinuz-2.6.35-22-generic root=UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.35-22-generic
}
### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###
### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry "Memory test (memtest86+)" {
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux16 /boot/memtest86+.bin
}
menuentry "Memory test (memtest86+, serial console 115200)" {
insmod part_msdos
insmod ext2
set root='(hd0,msdos4)'
search --no-floppy --fs-uuid --set ce42f8c9-20af-4641-a4f9-143814ea2f6d
linux16 /boot/memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###

### BEGIN /etc/grub.d/30_os-prober ###
menuentry "Windows Vista (loader) (on /dev/sda1)" {
insmod part_msdos
insmod ntfs
set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set 94cc802bcc800a26
chainloader +1
}
menuentry "Windows Vista (loader) (on /dev/sda2)" {
insmod part_msdos
insmod ntfs
set root='(hd0,msdos2)'
search --no-floppy --fs-uuid --set 04ca8347ca833448
chainloader +1
}
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries. Simply type the
# menu entries you want to add after this comment. Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f $prefix/custom.cfg ]; then
source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###

=============================== sda4/etc/fstab: ===============================

# /etc/fstab: static file system information.
#
# Use 'blkid -o value -s UUID' to print the universally unique identifier
# for a device; this may be used with UUID= as a more robust way to name
# devices that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
# / was on /dev/sda4 during installation
UUID=ce42f8c9-20af-4641-a4f9-143814ea2f6d / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=86793bfd-a5ce-41e2-8e53-9672c7897288 none swap sw 0 0

=================== sda4: Location of files loaded by Grub: ===================


284.9GB: boot/grub/core.img
199.2GB: boot/grub/grub.cfg
122.4GB: boot/initrd.img-2.6.35-22-generic
122.5GB: boot/initrd.img-2.6.35-24-generic
284.9GB: boot/vmlinuz-2.6.35-22-generic
284.9GB: boot/vmlinuz-2.6.35-24-generic
122.5GB: initrd.img
122.4GB: initrd.img.old
284.9GB: vmlinuz
284.9GB: vmlinuz.old
=======Devices which don't seem to have a corresponding hard drive==============

sdb

[Rubi1200]

When the computer starts and you see the menu options which entry for Windows have you been trying sda1 or sda2?

Just out of curiosity, try both and see what happens.

I still think there are files missing and I suggest you either contact the manufacturer or ask on a Windows forum since it seems, from what you told us, that Ubuntu can boot normally.

This one (http://www.sevenforums.com/) is supposed to be really good.

[Marcel_V]

I always boot sda1, since sda2 is the system recovery partition. sda2 seems to have the same problem too though. When I reset the entire system, Windows works just fine, no matter how many times I reboot. Only after installing Ubuntu do I get boot problems. The strange thing is, sometimes Windows loads and sometimes it doesn't. I have no idea what that means.

[Rubi1200]

I always boot sda1, since sda2 is the system recovery partition. sda2 seems to have the same problem too though. When I reset the entire system, Windows works just fine, no matter how many times I reboot. Only after installing Ubuntu do I get boot problems. The strange thing is, sometimes Windows loads and sometimes it doesn't. I have no idea what that means.
When you reinstalled, I assume you set Windows up first and then Ubuntu?

How did you create the partitions for Ubuntu?

I think I know what the problem might be:

/dev/sda4
This is your Ubuntu install. But, partitions in an extended partition are numbered from 5 and upwards. This may well be the source of the problem.

Please explain how you partitioned and we can work from there.

[Marcel_V]

The installation program partitioned it for me, I just specified the partition size. I chose "install alongside other operating systems" in the installation menu, then a slider appeared to adjust the partition size. That's all I needed to do.

[oldfred]

That it sometimes works, sounds even more like a duplicate folder in your windows. That sometimes it sees a good folder & works and other times sees the bad folder and does not work.

[Marcel_V]

After a long break I did some searching and I found EasyBCD. I fixed the MBR, installed EasyBCD and added Ubuntu to the boot menu. Everything works fine now, problem solved.
Thank you for your input, I've learned a lot.