There are several complications/problems that can occur while running Ubuntu in a dual boot/wubi configuration.

This article shows you how to fix them.

Wubi

Missing hal.dll

This is a frequent error seen on wubi installations. It leaves windows unable to boot and complains about a missing C:\windows\system32\hal.dll

hal.dll is the Hardware Abstraction Layer (just like linux has) for windows.

This problem can be fixed by using the following steps.

1. Boot up off a Ubuntu LiveCD
2. Under the "Places" menu, select your windows partition (it will only be shown by its partition size)
3. navigate to windows/system32/dllcache
4. copy hal.dll from there to windows/system32/
5. reboot.

Dual Boot

Resizing Windows Vista / 7 Partitions

Windows 7 / Vista will sometimes fail to boot easily after its partitions are resized using GParted.

This is due to the fact that Windows uses a very simple boot loader. A regular file system check is normal and to be expected on the first windows 7 / vista performs bootup because GParted programs Windows to do that by putting the 'dirty' flag in its file system metadata.

The Windows Users Way of Resizing

The Windows users way of resizing a windows 7 / vista partition is to

1. Go into the control panel
2. Select "classic view" or "icon view" (youll have to look around hard for this)
3. click on "administrative tools"
4. click on "computer management"
5. click on "disk manager" (or something similar)
6. right click on the windows partition and resize.

Everyone else just uses GParted or the built in partitioner in the Ubuntu installer.

Sometimes when using GParted Partition Editor, people forget or are not aware they should remove the checkmark from the 'align to cylinders' checkbox because Windows 7 and Vista partitions usually start in sector 2048 instead of sector 63 like other operating systems partitions.

This can get Windows boot loader temporarily out of sorts.

How To Recover

To recover from this boot problem, you can either

a) Boot from your recovery dvds

• Select "startup repair"

b) Download either

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

  For Windows 7 : http://neosmart.net/blog/2009/windows-7-system-repair-discs/

• Burn the ISO to a disc
• Boot up from it
• Select Startup Repair.

Links

• https://help.ubuntu.com/community/WindowsRecoveryCd

• NeoSmart Windows 7 Recovery Discs

• NeoSmart Windows Vista Recovery Discs