Case Studies – PC Doctor Godalming

Clone drive using DD

24/11/2025

Clone a drive using dd in Linux

In Terminal identify source and target drives:

sudo fdisk -l

Note the devices (e.g., /dev/sda, /dev/sdb).

Run DD to clone the drive:

sudo dd if=/dev/source of=/dev/target bs=1M status=progress conv=noerror,sync

Replace /dev/source and /dev/target with the correct device names, e.g./dev/sda, /dev/sdb

Wait for completion and sync data to force all pending writes in memory to be flushed to disk

sudo sync

Note optional arguments to clone a defective drive for recovery:

conv=noerror: continues copying after read errors instead of stopping
sync: Pads missing data with null bytes to maintain alignment
dd stands for “data definition”,

Access Windows drive C: from another Windows PC

10/11/2025

Connect to the shared root C:\ drive using the credentials of the source owner user who is a member of the Administrators group.

Circumvent Remote User Account Control (UAC) filtering, default in Windows for workgroups. This feature strips administrator privileges when you connect to a share from a different computer using a local account.

Two-Part Solution

Part 1: Disable Remote UAC Filtering (On Windows 10 Source PC)

This Registry change is required to allow a local administrator account (like yours) connecting from the network to retain its full administrative permissions,

Step-by-step guide to connect the Deco XE75 to a BT Digital Voice router

21/10/2025

Step-by-step guide to connect the Deco XE75 to a BT Digital Voice router, including the critical AP mode configuration.

Step 1: Connect the main Deco unit in initial setup (Router mode)

The Deco must first be set up in its default router mode before it can be switched to AP mode.

Download the Deco app from the App Store or Google Play and log in with your TP-Link ID.

USB WiFi adapter losing its settings after a cold boot

12/10/2025

The issue of a USB WiFi adapter losing its settings after a cold boot in Windows 10 is commonly linked to power management settings that cause the device to power down to save energy. To resolve this, you should disable power-saving features for the USB adapter and related USB hubs. Specifically, navigate to the device properties in Device Manager, go to the Power Management tab, and uncheck the option “Allow the computer to turn off this device to save power” for the USB WiFi adapter.

How to Hide the “Try the new Outlook” toggle

27/06/2025

If you wish to hide the New Outlook toggle or prevent the automatic migration, you can set a registry key. The specific key is:

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Options\General

Create a new DWORD type entry with the name “HideNewOutlookToggle” and a value of “1“.

This will hide the “Try the new Outlook” toggle. Conversely setting it to 0 or deleting the value will re-enable it.

Missing Windows Boot Manager or bootrec fixboot error

22/06/2025

The “bootrec /fixboot access denied” error in Windows occurs when the bootrec /fixboot command cannot access or modify the boot sector and similarly Windows Boot Manager missing in the BIOS Boot Order are often due to issues with the Boot Configuration Data (BCD) or partition structure.

To resolve this, try using bcdboot to rebuild the BCD store, or attempt to fix the issue using the Windows Recovery Environment

Here’s a breakdown of how to troubleshoot and resolve the issue:

Remove Change Search Settings from Firefox Homepage Content Search Suggestion List

09/06/2025

This fix works around the issue of Firefox randomly selecting “Change Search Settings” to search for the entered string in Firefox Settings when you want to search the web with the default search engine. When this happens you also lose the search string and have to retype it.

Place the following code in userContent.css or userChrome.css and place it in the chrome (lower case) folder within the Firefox default profile directory. If the chrome folder does not exist then create it.

* Update: best to have both userContent.css and userChrome.css in chrome folder as it is noticed that some pages,

Reset and Wipe your PC using Windows Reset

26/05/2025

The simplest way to wipe your PC to donate, recycle, or sell your PC, is to use the Windows 10 | 11 Reset option

Windows 10
Settings > Update & Security > Recovery
Click ‘Get started’ under ‘Reset this PC’

Windows 11
Settings > Windows Update > Advanced options > Recovery
Click ‘Reset PC’

When ‘Reset this PC’ dialog opens, click ‘Remove everything’
Click reinstall Windows from ‘Cloud download’ or ‘Local reinstall’ (faster)
In ‘Additional settings”

List LAN IP Addresses Host Names MAC addresses and Owners

02/05/2025

Linux script to discover active hosts and resolve IP, .local hostnames, MAC addresses, and owners

Install nmap and avahi-utils (if not already installed):

sudo apt update
sudo apt install nmap avahi-utils

Short nmap command to list IP, hosts, etc. but omits .local devices

sudo nmap -sn -R 192.168.1.0/24

# Terminal script to list IP Addresses, Host Names, MAC addresses and vendors
resolve_device() {
    local ip=$1
    echo "Resolving IP: $ip"
    local hostname=$(avahi-resolve -4 -a "$ip" 2>/dev/null | awk '{print $2}')
    if [ -z "$hostname" ];

Create Locally Trusted Host SSL Development Certificates

20/04/2025

Use mkcert to making locally-trusted host development certificates that avoids browser self-certification dialog warning and requires little or no configuration

Install mkcert:

sudo apt update
sudo apt install libnss3-tools
curl -JLO "https://dl.filippo.io/mkcert/latest?for=linux/amd64"
chmod +x mkcert-v*-linux-amd64
sudo mv mkcert-v*-linux-amd64 /usr/local/bin/mkcert

Install the local CA:

mkcert -install

Generates and installs CA cert/key pair (rootCA-key.pem,rootCA.pem) in system trust store – $CAROOT (defaults to ~/.local/share/mkcert)
Installs local CA in the Firefox and/or Chrome/Chromium trust store (requires browser restart)

Generate certificate and key file for locally hosted website:

mkcert example.org localhost 127.0.0.1 ::1

Creates two files: example.org+3.pem (certificate) and example.org+3-key.pem (private key).

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