Don't EVER do what I've just done on my computer!

[A31]

Don't EVER do what I've just done on my computer!
Ever fancied using a duall boot? I do fancy using one, daull booting between XP Pro and Vista Ultimate. Turns out it really messed up my ThinkCentre though...
What I did was rig up an external HDD to my computer and then reboot. I inserted the XP disc into my drive and then booted from it. I had Vista on my computer all ready and wanted to dual boot between XP and Vista. I installed XP on my external hard drive name EXT.80GB and let the installation process finish. I had NOT backed up any of the files on my Vista configuration btw. However, when the DOS part of the XP installation finished and the PC had to reboot, I was greeted by my friend, the BSOD...so I removed my XP disc and rebooted, BSOD came again, disconnected the external hard drive and then somehow my system became all corrupt (same corrupt file as the one that silly Acer laptop I treid to do the other day).

I then booted of the XP CD again and went into the XP installation repair, tried to repair what I had of XP, wasn't having ANY of it, so I then rebooted of XP disc AGAIN and then told it to save my XP files (the C:\WINDOWS files) in a folder called C:\XP so hopefully my Vista installation would stay ok. Currently, I have got further than I have done before in the last hour or so... oh yes, also forgot to tell you that when I had to reboot during installation I got a "daul booter" screen that said would you like run Microsoft Windows XP Professional OR Microsfot Windows XP Professional! (I chose Vista! ) No actually, it decided for me and the installation carried on WITHOUT any visits from the BSOD! Currently feeling VERY annoyed as once I've got XP up and running, I'll have to install Vista x64 Uprade again!! But so far going well (I'm using the ThinkPad at the moment! The joy of having two computers lol!)

I'll post up wheter it works (hope it does otherwise I will EXTREMELY annoyed and irritated at myself!) I'm just wondered why on Earth it installed XP on my C:\ drive and NOT my external (F:\)?? I told it to go to EXT.80GB F:\ drive, not my C:\ drive!!

[RealBlackStuff]

To make a long story short: you ALWAYS install the old(er) OS first, then the newer.
In your case, you would have had to uninstall Vista, then install XP, then reinstall Vista.

[A31]

Exactly right! (as my Vista Ultimate copy is an Upgrade which require you to go into your current OS, then install it) luckily when I do this dual boot thing for real, with my new HP, it'll have xp pro on it first, and then I'll make a Vista dual boot for it! I'll use the HP's 80GB SATA for the XP Pro and my 400GB SATA for Vista Ultimate.

Also couldn't install vista x64 so went for Vista x86 instead and it works fine now. Luckily I had the vast amjority of my old files thanks to the windows.old folder, which was 60.5GB!!

When I do turn on the ThinkCentre it does a multi boot screen with either "Vista" or "Earlier version", when I select earlier version it's actually XP but it's the corrupt version (the installation where I got visited by the blue screen of death)!, so I just select Vista... and it works... Roll on the new computer!