Hey, first-timer here.

Overnight my laptop was left to update itself as usuall, but when I got to it this morning I found it repeatedly flashing a BSOD with the error:

UNMOUNTABLE_BOOT_VOLUME

I have attempted countless boots into safe mode, all throw the same BSOD at me.
My machine is an HP Pavillion ze4900 model laptop running WinXP Home (well.. was).

I've tried a some "common remedies" but none seems to be effective at all..
Does anyone have an idea on how to recover from this, or is my laptop to hence-forth be known as a brick.

(If any solutions involve removing the HDD, you will need to explain in detail as I have not seen anything obvious on the underside)

Many thanks!

Please run CheckDisk from your Windows XP Home CD
Info here ("From Boot Up") http://www.techspot.com/vb/post694184-133.html

Many thanks for your (incredibly) quick response..

Unforntunately the Windows XP disc associated particularly to my laptop is not available..
Will any Windows XP Home disc suffice?

If I can get Check Disk to run, what should be a good outcome and what's condsidered a failure? (I've not done an out of windows check disk before and would like to know in advance as the only windows CD i have access to wont be available until this afternoon)

Again, a huge thanks for the speedy responses

Cheers,
Saldash

No problems, thanks for your questions

Actually any Windows XP CD will do, in actual fact on that link I provided above, you can use a number of different Boot CDs (but the process won't be the same for all of them)

CheckDisk from the Recovery Console (Windows Boot up CD) is quite standard and not normally an issue.

Further from there, you could try The Ultimate Boot CD, I have some info here on that as well http://www.techspot.com/vb/topic123957.html

Just to clarify, the laptop is booting as far as the windows logo and little progress bar.. it then stops - BSODs and reboots.

Safe mode - Gets as far as an AVG .sys file and then BSODs..

Does this sound like the HDD is still alive but the windows installation needs a repair? - If i used a 2.5 to 3.25" HDD adaptor could pluging in the laptop HDD via an IDE usb cable get my data back all in 1 piece?

Thanks

As stated this does not sound like Hardware

Yes you can use an adapter to "back up" your data, although I would suggest you just use The Ultimate Boot CD as linked exactly in the above guide (please read it all, even the part further down in that guide)

By the way, do not install AVG8 again, this Antivirus can corrupt a computer by allowing non detected Viruses into your computer, and usually corrupts network settings when a computer does get infected. Use Avira instead.

update

Just a quick update... i got my hands on a Windows XP home disc, and ran the check disk utility.

On firt run it told me that it seemed there were no errors and was running properly..
I didnt believe that for a second so I force scanned and it did come up with errors and attempted to correct them..

SOMEHOW i managed to manually repair the boot configuration and windows now boots into safe mode ( i havent tried normal yet)

So im going to plug in my 500Gb external and start copying over my files ASAP before globally formatting, and repartitioning the drive for a fresh windows install..

Im so releaved that what i cant remember i did worked ( o.o seriously!)
And I thank you Kim for giving a rather distressed individual a shove in the right direction!

I'll post again to say if ive completely saved the day or if my touch of magic was a never-lasting fluke.

Cheers!

Good idea

Also here's the exact steps (with pics) on re-installing XP Home clean

Microsoft's Windows XP Home Repair Install step by step (* Including Delete Partition)
http://www.windowsxphome.windowsreinstall.com/sp2sp3installxpcdoldhdd/indexfullpage.htm

* Warning deleting the Partition will remove all User data and Windows system files