This week, I installed Windows XP Pro via Boot Camp on a MacBook Pro with a new 500GB hard drive. I encountered some interesting trouble, but successfully got Windows going on the laptop and I'm passing on some of what I've learned to you.

The goal was to create a drive with 3 partitions: a boot volume, a Time Machine and secondary boot volume and a Windows volume. In real-world terms, there's about 465GB to divvy up among the partitions and I figured it this way:

Boot vol: 313GB
Time Machine and Secondary Boot vol: 120GB
Boot Camp: 32GB

Initially, I erased the drive, installed the OS and did some basic setup stuff, then made a clone of the boot drive (you'll see why when I get to the end), ran the Boot Camp Assistant, which repartitioned the drive for me and restarted from the Windows XP installer CD. I went through a normal-seeming installation, but then hit a roadblock.

Lesson 1: You can start up from a Windows boot disc by holding down the "C" key during startup or by holding down the Option key and selecting the Windows CD as the boot volume.

Hey! Just like with a Mac disc! But unlike a Mac disc, the software just wouldn't seem to install properly. I got a little ways into the Windows boot process, but then it stopped with a hal.dll is corrupt or missing error. There's advice on Apple's forums that those errors require a reinstall. Two reinstalls later, I went looking for better advice. Most fixes that I found for this error involved running the Recovery Console from the Windows installer CD. Okay, where's the Recovery Console? 'Turns out that there was no Recovery Console on my installer disc. Ouch!

Lesson 2: Buy a full retail version of the Windows install CD... (continued)

My copy of XP was an OEM version (legitimately purchased with PC hardware). The retail version has the Recovery console and can be used for repairing a drive. The OEM version that I had was a simple install/restore disc. That made things much harder when something went wrong.

That other fix was to delete and re-make the Boot Camp partition using the Windows installer. I'd read that you're not supposed to use the Windows XP installer to erase a Boot Camp volume, but it turns out that my information was outdated. And since it wasn't installing anyway, I figured what the heck. Aaaaannd after another install, the new error I got from Windows was that the partition was corrupt. Great. I tried making both FAT32 and NTFS volumes with the Windows installer. Same trouble.

Another trip back to the Mac OS. I used the Disk Utility to repartition the drive and give myself one Mac volume again. Then I used the Boot Camp Assistant to partition the drive again. This time, I decided to make the Boot Camp volume 30GB instead of 32GB. The reason why I did that was that I had read that the original version of Boot Camp calculated the volume size incorrectly so that the new partition was a nudge over 32GB and the FAT32 file system used for Windows couldn't deal with volumes that size.

Lesson 3: Don't use the default setup in Boot Camp.

After making a 30GB volume instead of a 32GB volume, I got Windows installed and it even started up... until it crashed with a black screen with a "press any key" message and failed to respond to keyboard input.

Still, I felt very close to a solution. One of the posters recommended erasing the volume using Windows Vista. I didn't have Vista handy, but I had recently downloaded and burnt the Windows 7 Preview. I had no plans to install Windows 7, but what would happen if I used the Windows 7 installer to remove and recreate the partition and then rebooted and installed XP?

Lesson 4: Don't give up.

It worked!Windows XP installed and started up without a hitch. I installed the Boot Camp drivers and Bonjour and quickly had it printing to my printer.

It was great until I rebooted into the Mac OS and used the Disk Utility to create the additional partition for Time Machine. Then, rebooting into Windows gave me the corrupt partition error I'd seen earlier. That was annoying, but not unexpected.

Lesson 5: The pain-free Boot Camp XP install.

I simply booted from the Windows 7 disc, removed and restored the Boot Camp partition, rebooted from the XP installer and then reinstalled XP. It went perfectly smoothly from there on in.

Lesson 6: Back up.

As soon as I was back in the Mac OS, I backed up my nice new working install of Windows XP with Winclone. Then I set Time Machine to back up just the Users folder to the extra Mac volume that I'd created. Finally, I cloned the backup of my original Mac OS install onto the Time Machine volume. What's the point? When you clone a bootable OS onto it, a Time Machine volume becomes bootable.

Now, while a user won't be protected against catastrophic failure while away from home with this laptop, they'll be able to rescue files that are accidentally deleted and there will be a clean OS to boot into and to run diagnostics from in case the boot volume gets messed up.

Eventually, this will be a triple-boot system with Snow Leopard, Leopard and Windows XP Pro. That's kind of cool.

Note: I used Boot Camp instead of Parallels or VMWare Fusion, but both Parallels and Fusion can use a Boot Camp volume instead of a virtual disk so the Boot Camp volume is potentially useful even when booted from the Mac OS.

Note2: Because I created the Windows volume using Windows 7, it's NTFS and not FAT32. This means that a user can't write to the Windows volume from the Mac OS. (Leopard can read NTFS volumes, but can't write to them.) Similarly, Mac OS volumes are not accessible while booted from Windows. Parallels or VMware both provide interoperability and there's also a commercial NTFS driver that fills the gap on the Mac side. There are a whole bunch of solutions for mounting Mac volumes from Windows, too. In a pinch, there are always flashdrives and Dropbox.