I just got a Dell Vostro 1400 and I'm trying to format the hard drive so I can replace XP Home with XP Pro.  The problem I'm having is that upon startup using the XP Pro CD, it's unable to find any hard drives in the laptop.  Obviously there's a hard drive there, I just don't know how to access it.
 
Does anyone know what can be done?  Thanks in advance!

Check you're BIOS and make sure the hdd is the second boot device after you DVD/CD

I made the secondary boot the hard drive and it didn't help.
 
When I put the XP Pro CD into the drive and load setup upon starting the computer, XP Pro goes through its normal processes before giving me the choice of setting up Windows or quitting setup, etc.  When I choose to setup XP, it says:
 
"Setup did not find any hard disk drives installed in your computer.
 
Make sure any hard disk drives are powered on and properly connected to your computer, and that any disk-related hardware configuration is correct.  This may involve running a manufactuer-supplied diagnostic or setup program.
 
Setup cannot continue.  To quit Setup, press F3."
 
There's no other option than F3 so I'm forced to quit.  The hard drive is clearly connected properly to the computer because if I just boot normally it heads right into the crappy version of XP Home that came pre-installed.
 
The only thing I can think of is that Dell put on some software to cause the hard drive to become hidden.  Does anyone have any other suggestions for what I should do next?

Can't imagine Dell would do something like hide the hdd, on the other hand, I wouldn't be shocked if Windows did.  If you now who the hdd mfg is, could run the diagnostic/repair software, which should let you format the drive

Okay, downloading the programs I found out it's a WD1200BEVS hard drive (so Western Digital, 120GB 5400RPM).  I also found two hidden partitions on the drive that are taking up approximately 4GBs.  I'm assuming it's these partitions that are causing the problem of Windows being unable to identify a hard drive but I'm wary to erase them offhand (I'm worried it'll do something to lock me out of the laptop).
 
How should I proceed?  Is there another way to format the drive outside of Windows besides using the setup disc?
 
And thanks for the responses - they've helped.

Also, as a quick update, I've found through Dell's setup that I have "Flash cache module" installed and enabled on this machine.  Isn't that a feature exclusively associated with Vista?
 
The reason I bring this up is because due to the fact that it's running the flash cache module, the hard drive can't run in ATA mode and must run in AHCI.  However, it states that if I change from AHCI to ATA mode it might prevent me from being able to load my OS and effectively lock me out of my machine (without a way to reinstall since I can't find the damn hard drive ).

If you mean the by Set Up disk, the one that came with the machine, it will likely just reinstall Vista.  Using the WD software should format the entire disk, which the XP install disk should recognized.  I'm assuming the XP disk is either OEM or Retail, i.e., didn't come with a prebuilt machine.  Worse case scenario, i.e., the disk isn't recognized when you try to reinstall off the disk that came with the machine, call Dell, act stupid - very easy for some of us, tell them Windows won't boot, you tried the restore disk, and it's saying that no hdd is recognized.  Very unlikely you'll have a problem running the WD software and a clean install of XP.  Download the most recent drivers for XP for that machine from Dell and put them on a CD before getting started.   Want to make sure there is XP drivers for that machine

We must have posted at the same time.  Can you disable the flash cache module in the BIOS?  Can you reset the hdd to hss to ACHI in the BIOS?  As long as you can get into the BIOS and change the relevant settings, you should be OK.  Again, on a new machine you can always call Dell support if worse comes to worse.  As long as you don't physical change or damage the machine and are installing the original OS, they'll provide support.  If you tell them you're installing a different OS or have a different one installed, they won't.  While Dell makes good laptop, they also do crap that really restricts what you can do

It turns out the AHCI thing was what was preventing me from formatting.  The minute I changed it to ATA mode, XP immediately recognized it and is allowing me to format it right now.
 
Thanks for your help, g-paw.  I don't think I would've come to the conclusions I came to without your input.

Glad it worked out for you