I googled the error (0xC0000005 windows install) and found a lot of post. The suggestion to clean the registry was ridiculous. In one case wiping the hard disk worked.
Unless your own scan of the same google results finds otherwise I suggest wiping the disk with DBAN or KILLDISK (download the iso, burn that to CD and boot from it). Then install Windows 7. Be SURE you've got all drivers needed (and that might be the difficult part).
Are you sure the laptop didn't come with a recovery disk? Didn't you make one? Google finds a lot of torrents to download one (but I don't recommend that; better order one from HP).
Doesn't the manual say anything about using a recovery partition? http://neosmart.net/forums/showthread.php?t=774 for example mentions the d:-drive as such for a dv6000.
Recovering Vista, then - if you prefer - upgrading to Windows 7 would solve the possible driver problem.
Kees
Last week my laptop (an HP Pavillion dv6000, running Vista) shut down while trying to install an update because the battery died. Ever since then I've been having problems. I decided to just back everything up and start over, rather than paying someone to fix all the problems. I got Windows 7, but every time I try to install it I immediately get the error code 0xC0000005 and don't know how to fix it. I was told to reformat my hard drive and try again, but my laptop came with Vista preinstalled. I don't have a disc, so Vista won't allow me to reformat my hard drive. If anyone has any suggestions on either problem- getting rid of my error code OR reformatting my hard drive, any help would be greatly appreciated.

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