Beuy's Blog

You need to log into safe mode of your family members computer, however their user account doesn’t have administration privileges, and they don’t know the password to the administrator account, worse still it’s not blank, password, or the name of the family dog!

A handy tool to deal with this problem is the Offline NT Password & Registry Editor, another bootable device that needs to load before the operating system. With this you can blank the administrator or change the password (Warning: I have never managed to change the password successfully, however blanking has always worked!) this will let you log into the machine to make the changes you need.

I highly suggest that a backup image of the machine be taken via a cloning tool before you make any changes with ONTPRE, there is always the slight possibility that something will go wrong and it’s much better to have a backup and not need it instead of finding yourself with a corrupt system and no backup.

A common problem that plagues large Windows Domains and Networks is the IP Address Conflict, this is when a device is trying to communicate to the Gateway or Primary Point of Contact, and is informed that the IP address it is using is the same as another device. This is usually confusing as DHCP is most commonly used in large networks.

In order to resolve this problem, it is first required that you understand the basics of IP addresses, if a machine receives a lease from a DHCP server with an IP address that reports a conflict, it is unlikely that the DHCP server is corrupted, but rather much more likely that there is another device on the network with a Static IP address.

The most effective way to correct this issue is to track down the device with the Static IP and change it’s IP to outside the DHCP range. Following is a true step-by-step troubleshooting method that I recently performed:

1. Change the workstation that is reporting the IP Address Conflict to a Static IP outside the DHCP range.
2. Delete the lease for the workstation from the DHCP server.
3. Ping the offending address to ensure that the device is still on the network.
4. Perform a Port Scan with a program like Nmap to identify the device, in my case port 80 was open, so I went to the URL of the device and confirmed it to be an IP based camera provided by a company called GeoVision.
5. Inform the owner of the device to change the IP to outside the DHCP range.
6. Change the original workstation back to DHCP and ipconfig /renew to request a new lease.

As with many problems, breaking down into layers is key to resolving the issue.