Windows 10 notes WORK IN PROGRESS

Managing Files
Environment Variables
- Command Snippets
Powershell Configuration
Useful Cmdlets
Troubleshooting
- Disabled Running Scripts

Managing files

List 10 largest files for C:\ in megabytes

  Get-ChildItem c:\ -r -ErrorAction SilentlyContinue –Force |sort -descending -property length | select -first 10 name, DirectoryName, @{Name="MB";Expression={[Math]::round($_.length / 1MB, 2)}}

Environment Variables

The commands below are used to modify existing Environment Variables.

Command Snippets

List Environment Variables
```
  Get-Childitem env: 
```
Permanantly append Variable to path
```
  setx MyVariable "MyPersistentValue" 
```

Add new path to system Path

  $newPath = "$env:Path;C:\NewPath"
  setx Path $newPath

Remove temporary Environment Variable from path
```
  Remove-Item env:MyVariable
```
Remove persistent Environment Variable from path
```
  setx MyVariable ""
```

Check if Environment Variable exists in a powershell script

  if($env:MyVariable) {
      Write-Output "MyVariable exists with value $env:MyVariable"
  }else { 
      Write-Output "MyVariable does not exist"
  }

Using an Environment Variable in a Script

  $env:MyVariable = "something"
  Write-Output "The value of MyVariable is : $env:MyVariable"

Add script to PATH temporarily to Current Session
```
  $env:PATH += ";C:\path\to\your\script"
```

Add script to users persistent PATH

  [System.Environment]::SetEnvironmentVariable("PATH", $env:PATH + ";C:\path\to\script", [System.EnvironmentVariableTarget]::User)

List current path
```
  echo $env:path 
```

Temporarily append Variable to path

  $env:path += ";C:\Program Files\GnuWin32\bin" 

Powershell configuration

Change Keybinds to Bash like keybinds

Check if $PROFILE variable exists
```
 echo $PROFILE
```
Open file in path listed in echo $PROFILE, in this case i’m using Vim but you can use any editor you like
```
 vim $PROFILE
```

Then , paste the following code into the file

 # Load PSReadLine (should already be loaded in most cases)
 Import-Module PSReadLine

 # Map Bash-like key bindings
 Set-PSReadLineKeyHandler -Chord Ctrl+a -Function BeginningOfLine       # Move to start of line
 Set-PSReadLineKeyHandler -Chord Ctrl+e -Function EndOfLine             # Move to end of line
 Set-PSReadLineKeyHandler -Chord Ctrl+k -Function KillLine              # Delete text from cursor to end of line
 Set-PSReadLineKeyHandler -Chord Ctrl+u -Function BackwardDeleteLine    # Delete text from cursor to beginning of line
 Set-PSReadLineKeyHandler -Chord Ctrl+w -Function BackwardKillWord      # Delete previous word
 Set-PSReadLineKeyHandler -Chord Ctrl+y -Function Yank                  # Paste the last cut text
 Set-PSReadLineKeyHandler -Chord Ctrl+l -Function ClearScreen           # Clear screen

Now, save the file and reload profile.

 . $PROFILE

If you receive an error like below :

 . : File C:\Users\username\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1 cannot be loaded because running scripts
 is disabled on this system. For more information, see about_Execution_Policies at https:/go.microsoft.com/fwlink/?LinkID=135170.
 At line:1 char:3

Follow the instructions under “Troubleshooting” using the link here : ERROR:cannot be loaded because running scripts is disabled on this system.

The $PROFILE variable is a variable that contains the path to your windows “profile”.ps1 , it can be named anything but this is where you would keep all your custom configurations. In my case the variable contains the path of : C:\Users\username\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1

Use bash like aliases in Powershell

I am a fan of how bash allowsy you to customize your experience using the beloved ~/.bashrc file. For powershell it’s the same process with a verbose syntax compared to bash. For this section I will put some examples below of alises you might want to add. The basic structure of an alias would look like the below

Alias syntax template

  Set-Alias -Name <name-of-alias> -Value "<value-of-alias>"

Remove an alias
```
  Remove-Item Alias:<alias-name>
```
Alias for Pre-installed Windows command

Let’s say we wanted to change the alias for Changing the execution policy for the current user. Open the file located in your $PROFILE variable ( check the above inline comments for further info on what this variable is ).

```bash 
Set-Alias -Name "Resolve-DnsName" -Value "dig"
```

Create alias for non-built in script

Powershell aliases were intended for running cmdlets, not custom commands. To get around this limitation, you may want to define functions for your custom scripts instead of using Set-Alias directly. Please see the below example for how I would do this using a python 3 script.
```
  function tfind{
      python3 "C:\Users\buhfur\tfind\tfind.py"
  }
```

Note : Aliases in powershell were intended for executing cmdlets and not executing scripts. To get around this you may need to define functions with the command used to execute your script using an alias. Please see the above example for how to do this.

Useful cmdlets

Below is a gathered list of all cmdlets installed by default on most powershell systems.

System Cmdlets

Get-Command: Gets all cmdlets, functions, workflows, aliases installed on your system.
Get-Help: Displays help information for cmdlets and functions.
Get-Process: Gets a list of all processes currently running on the local or remote machine.
Stop-Process: Stops a running process by its process ID or process name.
Get-Service: Gets the status of services on a local or remote machine.
Start-Service: Starts a stopped service.
Stop-Service: Stops a running service.

File and Directory Cmdlets

Get-ChildItem: Lists files and directories in a specified location.
Set-Location: Sets the current working location to a specified path (similar to cd).
Copy-Item: Copies an item from one location to another.
Move-Item: Moves an item from one location to another.
Remove-Item: Deletes files and directories.
New-Item: Creates a new item (file, directory, etc.).
Get-Content: Reads the content of a file.
Set-Content: Writes content to a file, replacing existing content.
Add-Content: Appends content to a file.

Networking Cmdlets

Test-Connection: Tests the network connection to a remote host (similar to ping).
Resolve-DnsName: Performs a DNS query for a specified name.
Invoke-WebRequest: Sends HTTP and HTTPS requests to web pages and retrieves content.
Get-NetIPAddress: Gets the IP address configuration for network adapters.
Get-NetAdapter: Gets the status of network adapters.

User and Group Cmdlets

Get-LocalUser: Gets local user accounts.
Add-LocalUser: Creates a new local user account.
Remove-LocalUser: Deletes a local user account.
Get-LocalGroup: Gets local groups.
Add-LocalGroupMember: Adds users to a local group.
Remove-LocalGroupMember: Removes users from a local group.

System Monitoring Cmdlets

Get-EventLog: Retrieves events from the event log.
Get-PerformanceCounter: Retrieves performance counter data.
Measure-Object: Calculates properties of objects (e.g., count, sum).

Automation and Scripting Cmdlets

ForEach-Object: Processes each item in a collection with a specified script block.
Where-Object: Filters objects based on specified criteria.
Select-Object: Selects specific properties from an object.
Sort-Object: Sorts objects by property values.
Export-CSV: Exports data to a CSV file.
Import-CSV: Imports data from a CSV file.

Security Cmdlets

Get-Acl: Gets the security descriptor for a specified item (file, folder, etc.).
Set-Acl: Sets the security descriptor for a specified item.
Get-Credential: Prompts for user credentials securely.

Windows Update Cmdlets

Get-WindowsUpdateLog: Retrieves Windows Update logs.
Install-Module: Installs PowerShell modules from the PowerShell Gallery.

Help and Support Cmdlets

Get-Command: Lists all available commands, including cmdlets, functions, and aliases.
Update-Help: Downloads and installs the newest help files for PowerShell modules.

Troubleshooting

Disabled Running Scripts

This error indicates the user does not have the execution policy set for a specific user to run scripts inside their session. To allow the user to run the spcified command / script. Follow the instructions below, make sure you’re logged in as administrator. If there are any scripts that can be used by the admin but not you, it’s likely something to do with the execution policy that’s been set.

Change Execution Policy to allow Local scripts

  Set-ExecutionPolicy RemoteSigned -Scope CurrentUser

Change Execution policy to allow user to run scripts from the internet
```
  Set-ExecutionPolicy Unrestricted -Scope CurrentUser
```

Bypass prompts for Internet Scripts

  Set-ExecutionPolicy Bypass -Scope CurrentUser

The ‘RemoteSigned’ policy allows scripts created on the local machine to run , while blocking scripts from the internet unless they are signed by a trusted source. The ‘CurrentUser’ scope only applies for the currently logged in user account , not the entire system Even when the Scope is set to ‘Unrestricted’ , you will still be prompted