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I’m Having Trouble Getting Access to a Second-hand Machine. What Can I Do?


I purchased a desktop, HP Pavilion with Win 7 from a soldier being deployed
to Afghanistan who needed the money to purchase an iPad. I’ve added myself as
the new administrator, but in every instance where my name appears, it’s linked
with his. Additionally, in certain tasks, I can’t complete it without his
authorization! I’ve tried a remove from ACE (Access Control Entry) and from ACL
(Access Control List) with no success. What’s the magic bullet?

In this excerpt from
Answercast #64
, I look at a second-hand machine that has blocked
administrator access.

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The big magic bullet

You’re not going to like the magic bullet. The magic bullet is to reformat
and reinstall Windows from scratch on that machine.

It really is the only safe way to take over a machine that formally belonged
to someone else. Unfortunately, that’s just the reality of it.

There is no way for example to rename the administrator account; or rename
what you’ll find on the hard disk for a previously existing account. Windows
doesn’t work that way.

You can create new accounts if you need to and give them new names – but
that will not take over the stuff that’s existing on that machine. You can even
make new accounts and make them the administrator on that machine – but that
doesn’t change the previously existing accounts and some of the kinds of issues
that you’re seeing.

Reformat and reinstall

So, what I strongly recommend (and it’s something that I recommend whenever
anybody gets a used machine) is that you reformat and reinstall
Windows from scratch.

I have an article on it, “How
do I gain administrative access to a second-hand computer?
” That is
basically what it’s going to tell you. The safest thing to do (both for your
protection and for the previous owner’s) is to completely erase that machine
and start over from scratch.

Regain administrator access

Now. If for whatever reason, that is not what you want to do: you want to
basically ignore that advice (and I kind of understand why people might want
to, because it is a fair amount of work), the other thing you can do
is to take over the true administrator account on that machine.

Then I would send you to an article on my site that has step-by-step
instructions on how to do that called, “How do I retrieve my Windows administrator password if I forgot it?

What that does is:

  • That will have you download a utility that you will burn on to CD.
  • Then you will boot this machine from that CD.
  • Then you will be able to reset the actual administrator password and become
    the true administrator on that machine immediately, and then do whatever you
    need to do.

As I said, you’re probably tired of hearing me say this, I don’t recommend
it because there’s just so much stuff about that machine that you don’t know:
you don’t what’s on it; you don’t know what malware may be on it; you just
don’t know! There’s so much you don’t know about that machine… that I
strongly recommend that you reformat it and reinstall from scratch instead.

Do this

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7 comments on “I’m Having Trouble Getting Access to a Second-hand Machine. What Can I Do?”

  1. Unfortunately, most of the computers that I have dealt with were purchased at some big box store like Best Buy or Staples and the previous owner did not have a copy of Windows to pass on with the machine. Thus, reformatting and reloading windows is not a true option for those machines without spending a hundred bucks for a copy of Windows.

    And yet it remains the only truly safe and secure option. Malware and worse can cost way more than a copy of Windows would. Alternately, install Linux, which is free. But ultimately this is why I so often harp on making sure that you get installation media when you purchase the machine, OR you immediately create an image backup of the pristine system.

  2. @John Germann

    Indeed, you would if you wanted to go out and buy a whole new license for Windows (along with the installation media) – It’s the license that costs the money, not the DVD with Windows on it. A brand-name computer from a big-box store will always have a license already (little sticker on the back, with the product key on it). As well, with Windows Vista (or newer) there are options to either burn a recovery disk (which you should do first thing when you fire it up – assuming you can log into Windows) or recover from a special partition on the hard drive (not quite as reliable as read-only optical media, but in a pinch it’ll do you, especially if you can’t log in. There should be a message that says something like ‘press F3 to recover’ early on in the boot process).
    If you have XP, there are less options, and short of finding a friend with a CD that you can borrow, you might want to consider upgrading or moving over to an alternative operating system, as Microsoft support is ending relatively soon.
    Hope this helps.

  3. One can download and burn to DVD the W7 “flavor” iso from Digital River that the used pc came with.
    Then, as Leo suggests, start a fresh install using the product key from the label on the unit to complete the process.

  4. Since disk drives are so cheap, I strongly recommend that any new installation also be to a new drive. The old one can be mounted later in case there are files that are needed. If files on it are inaccessible there are utilities to take ownership (TAKEOWN) and to change the access control (CACLS). I’ve had to do this more than once.

    I’ve actually got an article on the Takeown/Cacls process: How do I gain access to files that Windows says I don’t have permission to access?

  5. Or… every HP I’ve owned has a recovery partition that you can boot and restore the system to “as shipped”. Some of them have included lesser degrees of wiping including keeping user documents. I also bought some Lenovo laptops from a failed company and was able to put them back to the original XP Pro this way.

  6. Assuming one takes option 2 and changes the administrator, won’t a full scan with Malwarebytes and a full scan with a good anti-virus tool remove any resident ‘baddies?’ Might this might be a good option if one was giving away one’s old computer to a needy friend?

    No. The problem is that there’s no way to guarantee that all malware has been removed. One security maxim is that “once infected, it’s not your machine any more”. Using scanners to remove malware it a calculated bet – often a winning bet, but occasionally not when a machine reported as “clean” ends up still having malware in the form of rootkits or other things on it. Also, not everything is malware. Consider, for example, the ramifications of taking a second-hand machine that formerly contained pornography. Someone running an un-delete program could run into many things that would embarrass the heck out of you. Bottom line is when you get a second hand machine you don’t know what you’re getting in more ways that most people thing. DBan to erase it all, then reinstall the OS from scratch… it’s really the safest thing to do.



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