Windows XP Broken at Installation

Hello!  I recently switched from a (discontinued) competitor product to BitDefender.  I have old machines - some run Windows 7, some run XP.   My Windows 7 experience with BitDefender has been strongly positive - very few issues, and the chat support has helped me through them.  Windows XP, however...

I installed BitDefender on two Windows XP machines.  One is a home brew desktop, the other a Dell laptop.  Both have had varied histories - the laptop's had a fairly quiet life (used for accounting purposes every three months, almost no internet use), the desktop has had a much busier life.  Both had Norman Security Suite and Lavasoft Ad-Aware, which were removed during the BitDefender installation process.  After installation, after reboot (not completed immediately), neither machine will boot.

Both machines hang after mup.sys.  I cannot enter Safe Mode.  I have run chkdsk from the XP Recovery Console, so I don't believe it's a hardware error.  In fact, on the desktop, I've run every hardware test I can find - I've had it completely disassembled, checking to see if adding/removing any particular component has an impact.  Sadly, it doesn't.

I've contacted BitDefender support, I've had four suggestions:

1. Contact Microsoft for support of a product they stopped supporting years ago, and which was working fine until I installed third party software (BitDefender - note, this was a level one tech),

2. It may be a HDD/Hardware issue (Level 2 support - but no one can think it's likely that identical failures would occur in dissimilar machines after installing the same software - it's too much of a coincidence),

3. It may be that both machines had a significant rootkit, and removing that rootkit during BitDefender's installation scan may have killed it (again, Level 2, and unlikely - they've had very different experiences, it'd be odd that both would share the same rootkit issues),

4. It may be there was an incompatibility issue between BitDefender and and old Windows XP Driver.

I've spent the last four weeks trying to solve this, the last  1.5 I've spent trying to use Recovery Console, including a 'Windows Repair' on the laptop.  I seem to be locked out of C:Windows on the laptop - it wants a password to access that installation through Recover Console, and I don't have that password.


I'm not unhappy with BitDefender support here - I realize I'm working on an old OS which isn't widely supported anymore.  But I'm wondering if others might have encountered the same situations, or have other ideas.  For reference, my BitDefender ticket number was: 2017113007080003


Does anyone else have any further suggestions?  Machines are both XP SP3, BitDefender product installed was the 'BitDefender for Windows XP and Vista' option (I've purchased Total Security 2018).  I have no screenshots or warning messages, just an inability to get past mup.sys

Any assistance appreciated!


  • Sorin G.
    Sorin G.
    edited December 2017



    I am assuming you have not updated that machine to at least Windows 7 because its an old machine. Hardware issues cannot be ignored at this point.

    Firstly please ensure that you remove anything from your optical drive, silly I know, but make sure there isn't anything in it or any USB sticks/drives and try to boot afterwards.

    Secondly the issue with XP locking on that driver is a old one and is unrelated to Bitdefender. Moreover that the other security solutions were removed and asked for a reboot, the product is not installed at this point.

    If the above step yields no results I would recommend booting from your Windows XP CD/DVD and using the System repair option or the System Restore one.

  • Hello Sorin,

    You're right, both machines are older (though I didn't upgrade to 7 or beyond because there was no value in it - the software I use works better in XP and 7, and I've no intention of moving to the failed 8 or the more restricted 10 (I've one machine on 10, I don't like it at all)).

    But to have identical hardware issues across two very different machines (a laptop and a desktop) at the same time upon the installation of the same software would, you'd have to admit, be very unusual...

    I haven't had anything in the optical drives.  Other than, after the problems, the Windows CD.  And no USB HDD's/drives.  Not a silly question, boot sequence is important.

    The other solutions were removed, the scan was completed, both machines were left on for a period of time after installation.  The only part of the installation that wasn't completed was activating the licenses, as they wouldn't connect to the server.

    I've been attempting to repair it with Recovery Console on both machines, and also trying to do a Repair installation, but I've had no success doing that with either machine.  I don't want to have to format drives and lose data (some of which is significant, and not backed up).  And, given it's two machines with identical problems at the moment I installed one particular software package, I can't help but feel the software was at least a part of the cause.

  • Hello,


    Best that you try booting from the  install media and do the restore/repair which ever option is available to you. You mentioned you are being asked for a password, that is the main Administrator password you chose during the install of the OS.

    For the data itself, since you have more than one machine in the household I would recommend plugging the hard-drive to another machine and saving all your data. Afterwards a reinstall would be a option.

    Another alternative would be to install the OS over the old one, however this might or might not work, keep in mind that installed applications will surely malfunction but will give you access to the machine to back-up your important files.

    Keep in mind these are personal recommendations. You can also contact our support team via [email protected]