Updating and appending a CSV

Hello user4444,

Assuming that input file looks to something similar to this:

Username         Colum2 Column3 Column4 Column5
--------         ------ ------- ------- -------
tony.stark$      Data   Data    Data    Data
steve.rogers$    Data   Data    Data    Data
bruce.banner$    Data   Data    Data    Data
…$               …      …       …       …
natasha.romanov$ Data   Data    Data    Data
wanda.vision$    Data   Data    Data    Data
peter.parker$    Data   Data    Data    Data

One of the approaches would be the following:

$InputFile=Import-csv .\Users.csv
foreach($i in $InputFile){
 $UserInfo=Get-ADUser $i.Username.replace('$','')
 if($UserInfo){
   $i | Add-Member -NotePropertyName DisplayName -NotePropertyValue $($i.Displayname)
   $i | Add-Member -NotePropertyName GivenName -NotePropertyValue $($i.GivenName)
   $i | Add-Member -NotePropertyName Surname -NotePropertyValue $($i.Surname)
   $i | Add-Member -NotePropertyName Notes -NotePropertyValue ""
}else{
   $i | Add-Member -NotePropertyName DisplayName -NotePropertyValue ""
   $i | Add-Member -NotePropertyName GivenName -NotePropertyValue ""
   $i | Add-Member -NotePropertyName Surname -NotePropertyValue ""
   $i | Add-Member -NotePropertyName Notes -NotePropertyValue "No Information Found"  
 }
 
}

After that you can Export-Csv and have a file with consolidated Data.

Hope that helps.