If I saw that machine I'd write it needs a new motherboard.
So I'll start from the very beginning of the issue.
My girlfirend was using a laptop I have at home and she accidentally spilt some milk on the keyboard near the power supply input jack.
The laptop ran for a bit while my girlfriend tried to clean the spill and then it shut down. She rang me and I came home within half an hour or so and isolated the laptop from any power.
Now in hindsight I should have started taking the thing apart to clean straight away but I was busy for a couple of days so i set the laptop up in front of a fan to attempt to dry it before I took it apart. A few more attempts to turn it on (this may have been a mistake) once it had been in front of the fan for a couple of days saw it start all the way up to the desktop of Windows only to shut down by itself a couple of minutes later.
The charge light on the front stayed on for most of the time I had the fan in front of it but then began to flicker or flash until it just wouldn't turn on at all. Finally, before I stripped the whole thing down, the laptop would just hang at the windows loading screen during startup.
When I got the motherboard out I found funny coloured blue/red mould near the power supply jack (kind of expected since milk was on it). I soaked this part of the board in distilled water then cleaned it with isopropyl alcohol. I've put the laptop back together to find it still has the same problem which is:
The charge light comes on for a couple of seconds when you first turn the laptop on, then turns off (laptop continues to start up).
If you remove the AC power supply the laptop shuts off straight away.
The startup hangs at the Windows load screen in both Normal and Safe modes.
I see that you can replace the AC power supply jack easy enough but I've really got to the end of my ability when it comes to repairing laptops (this was the first time I ever took one apart).
If anyone knows of a quick fix or what is involved in fixing this some advice would be much appreciated.
I'm not afraid of hearing it's stuffed either (let's face it, its an old laptop) but the reason I want it fixed is because it is actually my dads and I want to exhaust every avenue before having to break the news!!
Any help very much appreciated