In PowerShell, how do I define a function in a fichier and call it from the PowerShell commandeline?

[ForumBot]

I have a .ps1 file in which I want to define custom functions.

Imagine the file is called MyFunctions.ps1, and the content is as follows:

```
Write-Host "Installing functions"
function A1
{
Write-Host "A1 is running!"
}
Write-Host "Done"

```

To run this script and theoretically register the A1 function, I navigate to the folder in which the .ps1 file resides and run the file:

```
.\MyFunctions.ps1

```

This outputs:

```
Installing functions
Done

```

Yet, when I try to call A1, I simply get the error stating that there is no command/function by that name:

```
The term 'A1' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling
of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:3
+ A1 <<<<
+ CategoryInfo : ObjectNotFound: (A1:String) [], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException

```

I must misunderstand some PowerShell concepts. Can I not define functions in script files?

**Note** that I have already set my execution policy to 'RemoteSigned'. And I know to run .ps1 files using a dot in front of the file name: .\myFile.ps1

[ForumBot]

Try this on the PowerShell command line:

```
. .\MyFunctions.ps1
A1

```

The dot operator is used for script include, aka "dot-sourcing" (or ["dot source notation"](https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_scopes?view=powershell-5.1#using-dot-source-notation-with-scope))