PS C:\Windows\system32> Get-PSRepository

Name InstallationPolicy SourceLocation

PSGallery Untrusted https://www.powershellgallery.com/api/v2/

TestRepo Trusted \NugetServer\BMNNuGet\packages

PS C:\Windows\system32> Find-Module * -Repository TestRepo

Version Name Repository Description

1.0.1 cConfigNode TestRepo Provides a way to manipulate nodes of the xml configu...
1.3.0 cNtfsAccessControl TestRepo The cNtfsAccessControl module contains DSC resources ...
3.2.0 xNetworking TestRepo Module with DSC Resources for Networking area

1.0.0 xReleaseManagement TestRepo Host a custom DSC Resource to transform files based o...
1.17.0 xWebAdministration TestRepo Module with DSC Resources for Web Administration

PS C:\Windows\system32> Find-Module xNetworking -Repository TestRepo
PackageManagement\Find-Package : No match was found for the specified search criteria and module name 'xNetworking'. Try
Get-PSRepository to see all available registered module repositories.
At C:\Program Files\WindowsPowerShell\Modules\PowerShellGet\1.0.0.1\PSModule.psm1:1360 char:3
+ PackageManagement\Find-Package @PSBoundParameters | Microsoft ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

+ CategoryInfo          : ObjectNotFound: (Microsoft.Power...ets.FindPackage:FindPackage) [Find-Package], Exception

+ FullyQualifiedErrorId : NoMatchFoundForCriteria,Microsoft.PowerShell.PackageManagement.Cmdlets.FindPackage

PS C:\Windows\system32> Install-Module xNetworking -Repository TestRepo
PackageManagement\Install-Package : No match was found for the specified search criteria and module name 'xNetworking'. Try
Get-PSRepository to see all available registered module repositories.
At C:\Program Files\WindowsPowerShell\Modules\PowerShellGet\1.0.0.1\PSModule.psm1:1772 char:21
+ ... $null = PackageManagement\Install-Package @PSBoundParameters
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

+ CategoryInfo          : ObjectNotFound: (Microsoft.Power....InstallPackage:InstallPackage) [Install-Package], Excepti 

on

+ FullyQualifiedErrorId : NoMatchFoundForCriteria,Microsoft.PowerShell.PackageManagement.Cmdlets.InstallPackage

PS C:\Windows\system32> $Credential

PS C:\Windows\system32> Find-Module xNetworking -Repository TestRepo -Credential (Get-Credential)
cmdlet Get-Credential at command pipeline position 1
Supply values for the following parameters:
PackageManagement\Find-Package : No match was found for the specified search criteria and module name 'xNetworking'. Try
Get-PSRepository to see all available registered module repositories.
At C:\Program Files\WindowsPowerShell\Modules\PowerShellGet\1.0.0.1\PSModule.psm1:1360 char:3
+ PackageManagement\Find-Package @PSBoundParameters | Microsoft ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

+ CategoryInfo          : ObjectNotFound: (Microsoft.Power...ets.FindPackage:FindPackage) [Find-Package], Exception

+ FullyQualifiedErrorId : NoMatchFoundForCriteria,Microsoft.PowerShell.PackageManagement.Cmdlets.FindPackage

PS C:\Windows\system32> Find-Module * -Repository TestRepo | Install-Module
PackageManagement\Install-Package : No match was found for the specified search criteria and module name 'xNetworking'. Try
Get-PSRepository to see all available registered module repositories.
At C:\Program Files\WindowsPowerShell\Modules\PowerShellGet\1.0.0.1\PSModule.psm1:1875 char:34
+ ... $null = PackageManagement\Install-Package @PSBoundParameters
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

+ CategoryInfo          : ObjectNotFound: (Microsoft.Power....InstallPackage:InstallPackage) [Install-Package], Excepti 

on

+ FullyQualifiedErrorId : NoMatchFoundForCriteria,Microsoft.PowerShell.PackageManagement.Cmdlets.InstallPackage

PackageManagement\Install-Package : No match was found for the specified search criteria and module name
'xReleaseManagement'. Try Get-PSRepository to see all available registered module repositories.
At C:\Program Files\WindowsPowerShell\Modules\PowerShellGet\1.0.0.1\PSModule.psm1:1875 char:34
+ ... $null = PackageManagement\Install-Package @PSBoundParameters
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

+ CategoryInfo          : ObjectNotFound: (Microsoft.Power....InstallPackage:InstallPackage) [Install-Package], Excepti 

on

+ FullyQualifiedErrorId : NoMatchFoundForCriteria,Microsoft.PowerShell.PackageManagement.Cmdlets.InstallPackage

when using publish module if a user has a space in their profile it fails to publish the module:
PS C:> Publish-Module -Tags Twitter -Name Posh-Tweet -NuGetApiKey xxxxxxxx-xxxxx-xxxx-xxxx-xxxxxxxx -Verbose
VERBOSE: The specified assembly 'C:\Users\Carlos Perez\AppData\Local\PackageManagement\ProviderAssemblies\nuget-anycpu.exe' is installed at top level directory. However it is recommended that the assemblies should be installed under its ProviderName\Version folder.
VERBOSE: Skipping previously processed provider 'NuGet'.
VERBOSE: Repository details, Name = 'PSGallery', Location = 'https://www.powershellgallery.com/api/v2/'; IsTrusted = 'False'; IsRegistered = 'True'.
VERBOSE: Repository details, Name = 'PSGallery', Location = 'https://www.powershellgallery.com/api/v2/'; IsTrusted = 'False'; IsRegistered = 'True'.
VERBOSE: Publish Location:'https://www.powershellgallery.com/api/v2/package/'.
VERBOSE: Module 'Posh-Tweet' was found in 'C:\Users\Carlos Perez\Documents\WindowsPowerShell\Modules\Posh-Tweet'.
WARNING: Tags are now supported in the module manifest file (.psd1). Update the module manifest file of module 'Posh-Tweet' in 'C:\Users\Carlos Perez\Documents\WindowsPowerShell\Modules\Posh-Tweet' with the newest tag changes. You can run Update-ModuleManifest -Tags to update the manifest with tags.
VERBOSE: Loading module from path 'C:\Users\Carlos Perez\AppData\Local\Temp\1622731006\Posh-Tweet.\Posh-Tweet.psm1'.
VERBOSE: Repository details, Name = 'PSGallery', Location = 'https://www.powershellgallery.com/api/v2/'; IsTrusted = 'False'; IsRegistered = 'True'.
VERBOSE: Using the provider 'PowerShellGet' for searching packages.
VERBOSE: Using the specified source names : 'PSGallery'.
VERBOSE: Getting the provider object for the PackageManagement Provider 'NuGet'.
VERBOSE: The specified Location is 'https://www.powershellgallery.com/api/v2/items/psscript/' and PackageManagementProvider is 'NuGet'.
VERBOSE: Searching repository 'https://www.powershellgallery.com/api/v2/items/psscript/FindPackagesById()?id='Posh-Tweet'' for ''.
VERBOSE: Total package yield:'0' for the specified package 'Posh-Tweet'.
VERBOSE: Repository details, Name = 'PSGallery', Location = 'https://www.powershellgallery.com/api/v2/'; IsTrusted = 'False'; IsRegistered = 'True'.
VERBOSE: Using the provider 'PowerShellGet' for searching packages.
VERBOSE: Using the specified source names : 'PSGallery'.
VERBOSE: Getting the provider object for the PackageManagement Provider 'NuGet'.
VERBOSE: The specified Location is 'https://www.powershellgallery.com/api/v2/' and PackageManagementProvider is 'NuGet'.
VERBOSE: Searching repository 'https://www.powershellgallery.com/api/v2/FindPackagesById()?id='Posh-Tweet'' for ''.
VERBOSE: Total package yield:'0' for the specified package 'Posh-Tweet'.
VERBOSE: Performing the operation "Publish-Module" on target "Version '0.1' of module 'Posh-Tweet'".
WARNING: This module 'C:\Users\Carlos Perez\AppData\Local\Temp\1622731006\Posh-Tweet\Posh-Tweet.psd1' has exported functions. As a best practice, include exported functions in the module manifest file(.psd1). You can run Update-ModuleManifest -FunctionsToExport to update the manifest with ExportedFunctions field.
Publish-PSArtifactUtility : Failed to publish module 'Posh-Tweet': 'File does not exist (C:\Users\Carlos).
'.
At C:\Program Files\WindowsPowerShell\Modules\PowerShellGet\1.0.0.1\PSModule.psm1:853 char:17
+ Publish-PSArtifactUtility -PSModuleInfo $moduleInfo `
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

+ CategoryInfo          : InvalidOperation: (:) [Write-Error], WriteErrorException

+ FullyQualifiedErrorId : FailedToPublishTheModule,Publish-PSArtifactUtility

NuGet feeds allow security around both listing/retrieving packages as well as pushing packages. NuGet.exe and other clients further allow you to persist credentials for listing/retrieving packages using the "nuget sources" command. (https://docs.nuget.org/consume/command-line-reference#sources-command)

This persistence is important for two reasons:

1) When you push a package to a secured NuGet feed, NuGet clients generally do a list/read operation first. That list/read operation doesn't contain any API key that you pass along in the push operation. In order for a push to succeed with an API key, you also need to have credentials set for the read operation. You can read about some folks who have been affected by that here: http://inedo.com/support/questions/2319

2) In an unattended/build server scenario, you need the ability to provide credentials for list/read and push in a non-interactive way. If the only way to provide credentials is interactive (e.g., Get-Credential) then there's no way to, say, enable a build server agent to automatically install required scripts to execute a build.

This may somewhat overlap with this other note about Register-PSRepository failing against authenticated endpoints: http://windowsserver.uservoice.com/forums/301869-powershell/suggestions/11678499-register-psrepository-fails-against-authenticated