I just started  learning powershell using Technet Virtual Labs

In this one lab the goal is to get all items in a directory then just view the extension object then  just list the unique extension so if a n extenstion exists 100 times the output will only show one

 

Here is the syntax:    get-childitem c:\windows\system | select-object extension | sort-object extension  -unique

The lab indicates that I am supposed to see all extenstions in the output, I am only seeing one file type

Extension
---------
.DRV

 

Does anyone have a clue as to why this is taking place ?

 

Welcome to PowerShell!

I tried that command on my local system and was able to list out five distinct file extensions. I've also tried it on several other directories, with it listing out the proper extensions.

Were you trying this in the virtual lab or on your machine?

use system32 not system

also... I think group-object is a better solution here
get-childitem c:\windows\system32 | group-object extension
or
get-childitem c:\windows\system32 | group-object extension | %{$_.Name}

I was running the lab on my own pc ....

I just realized that I had a typo at the end of the syntax ...  what is odd is that   power shell did not generate an error just odd results .. I retyped the command without a typo and it worked

 

 

For educational purposes, can you share the typo? It might be instructive to figure out what PowerShell thought you meant (i.e. why you didn't get an error message).