I am trying to update the PSFTP module from the gallery. I used Remove-Module, but these three (3) aliases remain. How can I remove them before installing the current PSFTP module?

Additional information

I am not sure how PSFTP got onto this machine. Using Uninstall-Module, even under Run as Administrator, does not work. How might I correctly uninstall this module?

The module directory does exist on the machine.

Remove-Module unloads a module, but doesn’t remove it from the filesystem.

With $PSModuleAutoLoadingPreference at its default (All), this means that the module and its commands are still discoverable, even if the module isn’t currently loaded (imported).

As it happens, this particular module exports only aliases, which is why only they show up in the output from Get-Command *ftp*.

While Get-Command is able to find aliases from not-currently-loaded (imported) modules, such aliases are not present in the Alias: drive and attempts to remove them with Remove-Item Alias:<name> or, more directly, Remove-Alias <name> fail.

If you want to uninstall the module before installing a new version – assuming you’ve installed it from the PowerShell Gallery, as you say (see update below) – use Uninstall-Module.

That said, in order to update an installed module, simply use Update-Module.
Note that this performs a side-by-side installation, however: while the newest version does take effect, the previous version is retained and requires manual removal, if desired.

If the module wasn’t installed from the PowerShell Gallery, manual deletion of its folder is required:

• Be sure that no other modules depend on the module to delete.
  • To find a module’s dependents, i.e., other modules that depend on it, use, e.g. (I’m using module PackageManagement as an example, which has module PowerShellGet as a dependent):
    
    Default

    Get-Module -ListAvailable | Where-Object { $_.RequiredModules.Name -contains 'PackageManagement' }

    1 2 3

    Get-Module -ListAvailable | Where-Object { $_.RequiredModules.Name -contains 'PackageManagement' }

    • Note, however, that there could be scripts that also rely on this module, and such uses would be much harder to detect (short of searching all scripts for #requires -Module directives, using -module statements, Import-Module calls, or simply calls to the module’s commands that relied on auto-loading the module).
  • To perform the inverse operation, i.e. to find a module’s dependencies, if any (the modules a given module itself depends on), use, e.g.:
    • (Get-Module -ListAvailable PowerShellGet).RequiredModules (there will be no output if there are no dependencies),
    • Similarly, as @lit (the OP) points out, you can query a module available in the PowerShell Gallery for its dependencies online; e.g.:
      Find-Module -IncludeDependencies PowerShellGet (this will list the module itself first, followed by its dependencies).
• Depending on the module’s installation location, you may need administrative privileges for removal (an elevated session).
  • This is definitely the case for C:\Windows\System32\WindowsPowerShell\v1.0\Modules\PSFTP.
    Note that, as a third-party module, PSFTP should never have been installed there, because C:\Windows\System32\WindowsPowerShell\v1.0\Modules ($PSHOME\Modules) is reserved for system modules (the ones that ship with PowerShell).
  • Once you’ve confirmed that it is safe to delete the module folder, use the following (remove the -WhatIf to perform actual deletion):
    
    Default

    Remove-Item -Recurse -Force -WhatIf C:\Windows\System32\WindowsPowerShell\v1.0\Modules\PSFTP

    1 2	Remove-Item -Recurse -Force -WhatIf C:\Windows\System32\WindowsPowerShell\v1.0\Modules\PSFTP

Determining a module’s location (installation folder):

• By module name (e.g., PSFTP):
  
  Default

  Split-Path (Get-Module -ListAvailable PSFTP).Path

  1 2	Split-Path (Get-Module -ListAvailable PSFTP).Path

  • -ListAvailable ensures that the module is found even if it is not currently imported, but only if it is is located in one of the directories listed in $env:PSModulePath.
  • Conversely, if a module is currently imported, but resides in a nonstandard directory, you most omit -ListAvailable in order to find it.
  • Multiple versions of a module may be installed and therefore be returned; the one with the highest version number is listed first.

• By the name of a command exported by the module (e.g., Send-FTPItem):
  
  Default

  Split-Path (Get-Command Send-FTPItem).Module.Path

  1 2	Split-Path (Get-Command Send-FTPItem).Module.Path

  • Get-Command finds the command whether or not the containing module is currently imported.
  • If a module containing a command by that name is currently loaded (imported), its path is returned.
  • Otherwise, if multiple module versions are installed, the effective one is reported, which is the one with the highest version number.