Solved Laptop stuck on bootloop

[Paulo27]

I was originally seeking help in the Vista forum but managed to find out the machine's OS is actually Windows 7, here's the original message with some updates:
Machine isn't mine, we borrowed it from our uncle for my sister to use.
After a couple weeks it stopped working out of the blue, she tells me she was using it one night and it had little battery left and it ended up running out and the machine shut down and she went to sleep, next morning it wouldn't boot.
I imagine the problem is the battery, I used Hiren's BootCD to test it a bit and everything seems fine, I ran a bunch of tests with Mini Windows XP and only thing that seems out of place is the fact that it won't detect a battery when using one of the apps it has that deals with the battery, the laptop does work without being plug in though so I don't know if that's really it.
I tried recovery mode on startup but that doesn't work either, it just goes back to bootlooping.
It's a Compaq.

On the Vista forum someone told me to try Startup Repair with a Vista disc since Vista is the original OS of the machine, obviously it didn't work since it has Windows 7 installed now.
Should I try the same with a Windows 7 disc for starters?

Any help would be appreciated.

 

[rvcjew]

I would try the startup repair. http://www.sevenforums.com/tutorials/681-startup-repair.html does the bios see your hdd, by bootloop do you mean that it shows starting windows then reboots.

 

[Paulo27]

Thanks, didn't know there was a system repair disc, but it didn't work, sadly, it gives a 0cx00000e9 error everytime (note that previously I tried a Vista disc (installation disc to try and use the repair function) and it worked fine, obviously it didn't actually work since it actually had Windows 7 installed but the disc booted up fine, might have been that I screwed up somewhere downloading or making the system repair disc).
I found a Windows 7 ISO though and will be trying that too in a couple hours.

What do you mean by BIOS seeing my HDD? Does it show up on the BIOS menu? It doesn't seem like it, unless I'm not looking hard enough or in the right place, running tests through the BIOS (Primary Hard Disk Self Test) says that there's nothing wrong with it though.
And by bootloop I mean that it starts, the Compaq logo shows up and it restarts right as it tries to move on, basically stuck on the start logo.
It also says "Prepare to boot to OS" in the corner in small letters for a second but never does.

 

[gregrocker]

Work through the steps for Troubleshooting Windows 7 Failure to Start

 

[Paulo27]

Had almost given up since I kept getting boot errors with every CD I tried but finally managed to boot one of them and it fixed the problem and now the laptop boots fine.
Thank you for the replies.

 

[rvcjew]

Good to hear it.