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PowerShell help files

Help files are the best way to get help (pun intended) in PowerShell. They provide the most intensive details about the cmdlet and includes overviews, detailed explanations, examples, and much more. As its name suggests, you get help by running the Get-Help cmdlet.

For people out there who love *NIX, Get-Help is the equivalent of man pages in the Linux or Unix environment. Actually, an alias of man à Get-Help exists in PowerShell (thanks to Brian Wuchner for pointing this out).

The first thing that you notice in PowerShell 3.0 onward is that all the help files are not included as part of the package itself. In order to use the full range and the updated help files, you need to get them from the Microsoft website. If you try to use Get-Help for a cmdlet for which the help files are not downloaded yet, you get a short help description and then the following notification:

So, you need to run Update-Help to update all the help files. What this command does is that it checks all the installed cmdlets and verify them against the online version. If it finds an updated version available online, then it downloads the updated version. So, when you run PS C:\ Update-Help, it updates the help files.

Remember that, since it will update the help files placed in the default system path, you need to have administrator rights to run this command, otherwise this command will run but will fail to put the files in the system directories. So, before you run this command, open and run the console as an administrator.

There are times when we do not have an Internet connection in a system, especially in data center environments. In such a situation, we can download the help files into a central repository and then later use that repository to update the help files. The first part can be done by running the Save-Help cmdlet:

PS C:\> Save-Help –DestinationPath <Path where to store the files>

Once the files are downloaded, you can use that location to update the help files:

PS C:\> Update-Help –SourcePath <Path where the help files are>

Tip

Note that Update-Help and Save-Help work only with XML-based help files. It is not available for comment-based help files. In the next section, we are going to talk more about comment-based help files.