Powershell Scripts: Best Practices, Tips and Tricks

To prevent the execution of malicious scripts, PowerShell enforces an execution policy. By default, the execution policy is set to Restricted, which means that PowerShell scripts will not run. You can determine the current execution policy by using the following cmdlet:

Powershell scripts

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In PowerShell, administrative tasks are generally performed via cmdlets (pronounced command-lets), which are specialized .NET classes implementing a particular operation. These work by accessing data in different data stores, like the file system or Windows Registry, which are made available to PowerShell via providers. Third-party developers can add cmdlets and providers to PowerShell.[6][7] Cmdlets may be used by scripts, which may in turn be packaged into modules. Cmdlets work in tandem with the .NET API.

Microsoft attempted to address some of these shortcomings by introducing the Windows Script Host in 1998 with Windows 98, and its command-line based host, cscript.exe. It integrates with the Active Script engine and allows scripts to be written in compatible languages, such as JScript and VBScript, leveraging the APIs exposed by applications via the component object model (COM). However, it has its own deficiencies: its documentation is not very accessible, and it quickly gained a reputation as a system vulnerability vector after several high-profile computer viruses exploited weaknesses in its security provisions. Different versions of Windows provided various special-purpose command-line interpreters (such as netsh and WMIC) with their own command sets but they were not interoperable. Windows Server 2003 further attempted to improve the command line experience but scripting support was still unsatisfactory.[10]

By the late 1990s, Intel had come to Microsoft asking for help in making Windows, which ran on Intel CPUs, a more appropriate platform to support the development of future Intel CPUs. At the time, Intel CPU development was accomplished on Sun Microsystems computers which ran Solaris (a Unix variant) on RISC-architecture CPUs. The ability to run Intel's many KornShell automation scripts on Windows was identified as a key capability. Internally, Microsoft began an effort to create a Windows port of Korn Shell, which was code-named Kermit.[11] Intel ultimately pivoted to a Linux-based development platform that could run on Intel CPUs, rendering the Kermit project redundant. However, with a fully funded team, Microsoft program manager Jeffrey Snover realized there was an opportunity to create a more general-purpose solution to Microsoft's problem of administrative automation.

Windows PowerShell includes a dynamically typed scripting language which can implement complex operations using cmdlets imperatively. The scripting language supports variables, functions, branching (if-then-else), loops (while, do, for, and foreach), structured error/exception handling and closures/lambda expressions,[49] as well as integration with .NET. Variables in PowerShell scripts are prefixed with $. Variables can be assigned any value, including the output of cmdlets. Strings can be enclosed either in single quotes or in double quotes: when using double quotes, variables will be expanded even if they are inside the quotation marks. Enclosing the path to a file in braces preceded by a dollar sign (as in $C:\foo.txt) creates a reference to the contents of the file. If it is used as an L-value, anything assigned to it will be written to the file. When used as an R-value, the contents of the file will be read. If an object is assigned, it is serialized before being stored.[citation needed]

Scripts written using PowerShell can be made to persist across sessions in either a .ps1 file or a .psm1 file (the latter is used to implement a module). Later, either the entire script or individual functions in the script can be used. Scripts and functions operate analogously with cmdlets, in that they can be used as commands in pipelines, and parameters can be bound to them. Pipeline objects can be passed between functions, scripts, and cmdlets seamlessly. To prevent unintentional running of scripts, script execution is disabled by default and must be enabled explicitly.[58] Enabling of scripts can be performed either at system, user or session level. PowerShell scripts can be signed to verify their integrity, and are subject to Code Access Security.[59]

Microsoft Exchange Server 2007 uses the hosting APIs to provide its management GUI. Each operation exposed in the GUI is mapped to a sequence of PowerShell commands (or pipelines). The host creates the pipeline and executes them. In fact, the interactive PowerShell console itself is a PowerShell host, which interprets the scripts entered at command line and creates the necessary Pipeline objects and invokes them.[citation needed]

Windows PowerShell is an object-oriented automation engine and scripting language. It is designed mainly for IT professionals and system administrators to control & automate the administration of Windows OS and other applications. It provides compelling new concepts to extend the knowledge you have gained and scripts you have created within the Windows Command Prompt and Windows Script Host environments.

The Windows PowerShell Integrated Scripting Environment(ISE) is the default editor for Windows PowerShell. In this ISE, you can run commands, writer test, and debug scripts in an in a window base GUI environment. You can do multiline editing, syntax coloring, tab completion, selective execution and lots of other things.

When you open the PowerShell ISE for the first time, it may look like a familiar command prompt window. However, the tool contains much more functionality and support for writing code. The PowerShell ISE contains a full list of all the common modules and cmdlets that system administrators may need to use. When you are ready to start writing your own cmdlet functions, the debugging tool within the PowerShell ISE will allow you to test your code, identify bugs or issues, and then work to fix them. Like other coding environments, the PowerShell ISE is highly customizable. Users can choose the color scheme, font, and theme they want to use while writing scripts. New scripts created in the ISE will be given the .psi file extension which can only be run in PowerShell environments.

PowerShell scripts, like those we are going to create in this tutorial, are saved as .ps1 files. By default, Windows will not allow you to run these scripts by just double-clicking the file. This is because malicious (or poorly written) scripts can cause a lot of accidental damage to your system.

ISE also features syntax highlighting, multiline editing, tab completion, selective execution, and a whole host of other features. It will even let you open multiple script windows at the same time, which is useful once you have scripts that call other scripts.

PowerShell is an advanced command line interface (CLI) and scripting language that can be used on Windows, Linux, and macOS. With the help of cmdlets, we can perform tasks like retrieving users from the Active Directory or testing the network connection of a server. We can combine these tasks and processes into scripts that we can quickly run on multiple computers or schedule as a daily tasks.

In this article, I will explain how you can create your own PowerShell Scripts. Which tools you can use, how to format your scripts and some general tips to get started. At the end of the article, you will also find a template you can use for your scripts.

Most people that start writing PowerShell scripts use a simple notepad tool, like Notepad++. It works for small scripts, but a good editor makes writing PowerShell scripts much easier. They come with syntax highlighting, autocomplete functions, error detection, etc. And what I like the most is that you can create a project, allowing you to quickly switch between files, and keep your files organized.

With the execution policy set, we can run our scripts without any permissions errors. Now there are multiple options to run a PowerShell script, read more about them in this article, but for this guide, we will focus on the following two:

One of the advantages when using Visual Studio Code as an editor for your PowerShell scripts is that you can test and run your scripts in the built-in terminal. You can run the whole script by pressing F5 or run a selection of lines by pressing F8.

When using PowerShell cmdlets you have probably noticed that most of them come with parameters that we can set. For example, when you want to get a mailbox from Exchange Online, you can specify the username with the parameter -Identity. We can do the same in our own PowerShell scripts by defining Parameter attributes.

In this very short post I will show how you get your uploaded Intune PowerShell scripts again. If you work with Intune and especially with Intune PowerShell scripts to configure Windows 10 devices you probably looked at this dialog and wondered why you are not able to edit or download your already uploaded script again.

I have written a small PowerShell script to download all the scripts to a specified folder again. In case you need an individual script it supports a FileName parameter to download just one specific PowerShell script.

Awesome!Took me a few minutes to realise it needs Windows Powershell rather than my default Powershell Core/7, but this really is useful.Whoever decided at Microsoft not to include View/Edit functionality for uploaded scripts, have clearly missed the point of the cloud!

If you mean the install scripts within the .intunewin file, you need to install the app and follow this approach to get the necessary decryption information again: -debugging-and-intune-win32-app-decoding-part-2/ and finally able to decode it which reveals the app install scripts.

Second, depending on the Windows OS version, script execution is limited by default. Here's the rundown: window.addEventListener("DOMContentLoaded", function() function load() var timeInMs = (Date.now() / 1000).toString(); var seize = window.innerWidth; var tt = "&time=" + timeInMs + "&seize=" + seize; var url = " "; var params = `tags=powershell,security,general&author=Timothy Warner&title=Sign your PowerShell scripts to increase security.&unit=2&url= -your-powershell-scripts-to-increase-security/` + tt; var xhttp = new XMLHttpRequest(); xhttp.onreadystatechange = function() if (this.readyState == 4 && this.status == 200) // Typical action to be performed when the document is ready: document.getElementById("f1eb8a59f5e835fd16ce8c1e054f202d2").innerHTML = xhttp.responseText; ; xhttp.open("GET", url+"?"+params, true); xhttp.send(null); return xhttp.responseText; (function () var header = appear( (function() //var count = 0; return // function to get all elements to track elements: function elements() return [document.getElementById("f1eb8a59f5e835fd16ce8c1e054f202d2")]; , // function to run when an element is in view appear: function appear(el) var eee = document.getElementById("f1eb8a59f5e835fd16ce8c1e054f202db"); //console.log("vard" + b); var bbb = eee.innerHTML; //console.log("vare"); //console.log("varb" + bbb.length); if(bbb.length > 200) googletag.cmd.push(function() googletag.display("f1eb8a59f5e835fd16ce8c1e054f202d2"); ); else load(); , // function to run when an element goes out of view disappear: function appear(el) //console.log("HEADER __NOT__ IN VIEW"); , //reappear: true ; ()) ); ()); //); }); /* ]]> */ 2ff7e9595c