CMOS battery problem


Desktop PC stops working for no apparent reason. Doesn’t power on.


Tested power supply, power button, CPU, RAM, all fine.


CMOS battery! PC would boot if the battery was removed. With the battery inserted the system wouldn’t power on. Replaced the CMOS battery, but the problem persisted. Perhaps there is corrosion somewhere near the battery socket which causes this. I just left the battery out.

Current password is not correct

What The Error Message Said..

When starting windows you get this message at the login prompt:

“When trying to update a password, this return status indicates that the value provided as the current password is not correct.”

Why Did This Happen?

Most likely, I was trying to recover the password.


Replace the SECURITY/SAM file that lives in C:\WINDOWS\system32\config


To do this you need to access C drive in your computer without running Windows that is installed on that C drive. You can start the computer using a boot disk such as BartPE (see Google for detailed instructions). You can also move the disk to another computer and make the changes on that computer (see Google for detailed instructions).

Where do I get the SECURITY and SAM files?

If you are pretty stuck, try getting these from a fresh install of the OS you are working on (most likely this was Windows XP). Otherwise you should have a backup of these files since you were smart and backed them up before you messed about with them.

Cloning when you’ve forgotten to sysprep

If you need more help with any of this post please leave feedback


Cloning a hard drive means making an exact copy of a disks contents so that you can either backup or migrate your disk. This post is about cloning a windows partition so that you can run it from a different PC with different hardware on it. There is a useful section at the end, which will help you get into windows if you’ve forgotten to sysprep.


An easy piece of software to use is Ultrasoft Snapshot. Then use Microsoft sysprep utility to prepare the system for cloning. Use ‘snapshot’ to clone the partition to a backup hard drive. Restore the backup to a new disk.

If you haven’t run sysprep, and you no longer have access to the old machine, there’s some help to get you going in the trouble shooting section.

Microsoft sysprep

Microsoft have a page on sysprep. I forgot to use sysprep (hence this post) so you’ll have to google this section. Good Luck.

Ultrasoft Drive Snapshot

Use the ‘snapshot’ software from a startup disk in your original machine (eg bartpe) or by installing the original hard drive in another pc (let’s call it the host pc) and running ‘snapshot’ on the host machine. This is required because snapshot needs exclusive access to the source hard drive partition (the one you’re cloning), so you can’t be running windows off the drive you’re cloning whilst cloning.

You need the same amount of space free on your target hard drive partition as the source partition. If you have alot of free space on the source partition, it might help to resize it, eg using Partition Magic.

Use the ‘snapshot’ program to extract the cloned partition to the target hard drive. You can then boot into your target machine and finish. If you have trouble booting, mark the partition as active (can be done from boot cds, or installing drive in different machine and using the computer manager from the windows control panel.) Make sure the MBR has a working boot loader (eg use fixmbr from windows installation cd restore mode to reinstall bootloader.)

Troubleshooting ie forgetting to sysprep

If you cloned the partition and tried to boot it without sysprep’ing before cloning you will probably get problems starting the computer. It either restarts endlessly, or you get a blue screen (STOP 0x0000007B messages indicating problem with boot drive).

This usually happens because windows has problems starting in the new machine, as it is still setup for the old machine. One way to solve this problem is to install windows on your target machine in a new & empty partition. Then you need to copy over the system/sam/ security files from C:\windows\system32\config over to the problematic install. This will effectively overwrite the data windows keeps about the system hardware. I already had a windows installation on my target machine, so I copied these files over, and in my case this allowed me to boot into the cloned windows partition!

The only problem then remaining is that you might have registry entries in your old config files that are required by the software you had installed. These have to be manually sorted out by mounting the hives in regedit and copying the required data out. This is possible for a few registry entries (eg Windows Services entries etc.) but it’s probably too much hassle otherwise.


My problems were solved after copying over the configuration files, and fixing a few registry entries.

If you have time, instead of overwriting the entire SAM/SECURITY/SYSTEM hives, only overwrite the sections containing hardware information. Which sections are those? No idea, you’ll need to find out. Copy out enough registry entries to get it to boot (may only be those regarding chipset/graphics card/hd.)

Otherwise, find a guide on sysprep’ing after cloning and try that. Oh and let me know if that works.

Using mplayer/mencoder to convert to an MPEG

MEncoder is a useful media encoder that comes with MPlayer The Movie Player

To use, you’ll need to download and install MPLAYER as well as the extra plugins. You may also need Real Player, Quicktime, Windows Media Player installed (or an alternative.)

OK I’m always having to lookup the mencoder flags for encoding video files, so heres a useful example:

c:\mplayer\>mencoder.exe input.file -of mpeg -ovc lavc -oac lavc 
                  -lavcopts vcodec=mpeg2video:acodec:mp2 -o output.file

of = Output File ovc = Output Video Codec

The rest of the options can be looked up.