When querying a PowerShell object, it only returns a few essential properties by default. For example, querying the W32_ComputerSystem class with Get-WmiObject cmdlet only returns properties like Manufacturer, ComputerName, TotalPhysicalMemory, etc.
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To get the full list of the properties of Win32_ComputerSystem class, you can pipe the result to Format-List, like below.
Get-WmiObject -Class "Win32_ComputerSystem" | Format-List *
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You can even use the wildcard to narrow down the properties you are only interested in, such as below to list all Power-related properties.
Get-WmiObject -Class "Win32_ComputerSystem" | Format-List Power*
If you just needed the list of the properties without the actual value, pipe the result to Get-Member instead.
Get-WmiObject -Class "Win32_ComputerSystem" | Get-Member
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But neither would work for the objects that need additional module to get access to. For example, piping the Get-ADComputer cmdlet to Get-Member or Format-List only gets a small subset of properties of an AD computer object.
Get-ADComputer -Filter * | Get-Member.
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Instead, use this to get the full list of properties with values.
Get-AdComputer -Filter * -Properties *
Or, pipe the result to Get-Member to just get the full list of available properties. There are a ton of them in AD Computer object.
Get-ADComputer -Filter * -Properties * | Get-Member
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