There are a few different versions that you can download, a 1+ GB version that works for 64 bit and 32 bit, and a much smaller 400+ MB version just for 32 bit, which is what I downloaded.

I ran the setup, but it said my language wasn't supported. I have a US English version, so that was kind of weird... So I downloaded the other 1+ GB version and tried that. Same issue. Hmmm....

Finally, I figured it out. I have a Swedish language pack installed on my Vista (because I can say things like hurdy burdy and I can cook Swedish meatballs), and that was it: since the Service Pack does not support Swedish, it wont install. So I uninstalled my language pack (and can no longer spell check hurdy burdy), and after a mandatory reboot, the installer launched with no complaints.

Next up it told me I needed 7GB of free disk space. No such luck, especially with the 1 GB upgrade I just downloaded... so I deleted it, and re downloaded the 300 MB version directly onto a memory stick, and spent half an hour cleaning temp files and other junk. Now I had the required disk space to spare, plus 2 or three extra bytes, and set off to upgrade my system.

The installer does warn you that the upgrade will render your computer unusable for an hour or more, and will require multiple reboots, and that turned out to be just the case...

I was a little worried about installing from a USB memory stick, thinking the install might get into trouble when it first rebooted. But it seemed to do OK, copying a whole bunch of files off the memory stick onto my disk, which took half an hour or so, and then rebooting.

After the first reboot it went through a series of bewildering status messages, like "Step 1 of 3, 10% complete...", followed by other percentages, and then just going back to Configuring this, or Configuring that, followed by reboots and a scary moment where 70 000 DLLs flashed by in some kind of DOS prompt mode, followed by some registry operations. I crossed my fingers all the way through it, sacrificed a goat, and resisted the temptation to rebel against the "Do not turn off your computer" warning and turn it off just to see how well it would recover...

About an hour later, as promised, the final reboot was done, and then it appeared to upgrade user settings in much the same way as when a brand new user logs on for the first time, and then after logging in it looked like MSN Messenger got upgraded by some Windows installer task.

And then there was my desktop! Nothing appeared to have changed. I tried all my favorite programs (exciting things like Office 2007 Excel and Word, SQL Server 2005 Management Studio, Visual Studio 2008, Remote Desktop Connection)... all worked well. I had a minor heart flutter when I could not debug my web application in Visual Studio, but that turned out to be because Internet Information Server did not start up automatically after the upgrade.

Initially, I didn't see much of a difference in anything, but now, after a few hours, my system actually feels a lot faster than it was. I will blog about any breaking issues or major changes I see, but for now, it seems like I have survived the upgrade and lived to tell the story!

Note: My colleague Steve Trefethen was not as fortunate with his upgrade, he ended up having to uninstall the Service Pack due to problems executing Sleep and Resume with an external monitor connected. Read about it here...