I sold a laptop on here back in December a
HP Compaq Presario CQ61-223SA

It was a fresh install of Windows 7 on it, and had no user password set or Admin password.

Now 5 months later the buyer has contacted me and, this laptop has started asking for a Admin password and will not let him log on to laptop.

This is a new one on me, I have never heard of a laptop setting it's own password.

Any one any ideas please.
When windows was installed, no password was set.

It wouldn't, Virus/Spyware or User Error.

Windows password or BIOS?

Windows password.

Password rest via boot-cd would be my first suggestion.

Something like this;
http://www.howtogeek.com/96805/how-to-reset-your-windows-password-without-an-install-cd/

TBH, it has been 5 months and has only just contacted you with this problem. Unless you added you would be tech support for x amount of months in the advert details I would say it is their problem.

Unless of course they want to pay for your time to sort it

boot from windows 7 DVD press shift f10 when you get the install screen

type

rename d:\windows\system32\utilman.exe d:\windows\system32\utilman1.exe

copy d:\windows\system32\cmd.exe utilman.exe

then reboot
click the blue square bottom left

type net user THEIRUSERNAME 1

then press enter

their new password is 1

PS charge em £20 it's their fault!

http://pcsupport.about.com/od/toolsofthetrade/tp/passrecovery.htm

I am happy to try to sort it for them, they bought it from me, so am happy to help.

Of course, but having been there and done that with this exact type of thing, 99% of people will abuse your kindness..

I get people who I fixed computers for years ago as a freebie favour ringing me asking if I can fix TV's, DVD Players, washing machines, etc. On the hope I can and will do it for another freebie.

Not everyone is the same.

No, not everyone

I have now fixed this.

WHich method did you use

The op password got me into laptop after going in to safe mode, but password would not log on to normal windows, as user account profile had gone.

I then used system restore back to the 10th May.

If he can't get into Windows then he can get an Ubuntu Live CD. (it doesn't matter which version) Boot into Ubuntu, access his Hard drive and retrieve his data to an external drive, then format the Laptop and re-install windows.
If his data isn't an issue, he can create a Windows user account and continue to use the old installation. Not my choice though, If it's locked him out once, it'll do it again.

What did this person do to make that happen?
I only ask so I can make sure I don't do anything like it.
I have managed to do daft thing in the past,so you never know