When you post code please use the "Code Sample" editor. The icon is the 5th from the left on the Format Bar and has the graphic "101 010". The normal editor makes a mess of code, as you can see by looking at your post!

In any case, is this more-or-less what you want to do?

 $f1 = [PSCustomObject]@{Hash = "abc"},[PSCustomObject]@{Hash = "def"},[PSCustomObject]@{Hash = "ghi"},[PSCustomObject]@{Hash = "jkl"}
 $f2 = [PSCustomObject]@{Hash = "abc"},[PSCustomObject]@{Hash = "xyz"},[PSCustomObject]@{Hash = "ghi"},[PSCustomObject]@{Hash = "jkl"}
    
 $f1p = $f1.psobject[0].Properties.name | Sort-Object
 $f2p = $f2.psobject[0].Properties.name | Sort-Object
    
 $x = Compare-Object $f1p $f2p
 if ($x.Length -ne 0){
     Throw "Properties are not the same!`r`n$f1p`r`n`r`n$f2p"
 }
    
 Compare-Object $f1 $f2 -IncludeEqual -Property Hash |
     Where-Object {$_.SideIndicator -eq "=="} |                  # just find what's equal
         Select-Object Hash |
             Export-Csv c:\junk\equalvalues.csv -NoTypeInformation
    
 Compare-Object $f1 $f2 -Property Hash |
     Where-Object {$_.SideIndicator -eq "=>"} |
         Select-Object Hash |
             Export-CSV c:\junk\NotInReferenceSet.csv -NoTypeInformation
    
 Compare-Object $f1 $f2 -Property Hash |
     Where-Object {$_.SideIndicator -eq "<="} |
         Select-Object Hash |
             Export-CSV c:\junk\NotInDifferenceSet.csv -NoTypeInformation

Hi,

Its nearly there but I need to have the information displayed on the screen and keep the outcomes on a csv file.

The code looks good

Hello @Ed7

I would use the Compare-Object: https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/compare-object?view=powershell-7.2&viewFallbackFrom=powershell-6

For example I have this process for disabled users in my AD:

 TEST_AD.csv - this is my csv file export from AD from all my 'active' users. (System of Record).
 TEST_APP.csv - this is my csv file from the application.
 TEST_DISABLED_APP_USERS.csv - this is my csv file that I would upload to the application to disable any users not found in the TEST_AD.csv but are found in the TEST_APP.csv file.
    
 $ADCSV = Import-CSV -Path "C:\temp\TestCSV\TEST_AD.csv"
 $APPCSV = Import-CSV -Path "C:\temp\TestCSV\TEST_APP.csv"
 #for the compare I chose the "Email" header in the CSV file as my 'primary key'.  Something you know will exist to identify items (users) in each file that must exist in both files.
 $compareCSV = Compare-Object $ADCSV $APPCSV -Property Email -IncludeEqual -PassThru
 $output = ForEach ($item in $compareCSV) {
    
     If ($item.SideIndicator -eq "=>") {
         #this item (aka User) exists in the 'difference set' (TEST_APP.csv file) so we'll need to add them to our export CSV.
         [pscustomobject]@{
             #needed to create our output csv file.
             #first column is the export CSV headers, second (after '=') is the values/data.
             #remove any unnecessary headers/values that the upload file doesn't need.
             "Employee ID"     = $item.'Employee ID'
             "First Name" = $item.'First Name'
             "Last Name" = $item.'Last Name'
             "Display Name" = $item.'Display Name'
             "Telephone" = $item.Telephone
             "Email" = $item.Email
             "Street" = $item.Street
             "City" = $item.City
             "State" = $item.State
             "Zip Code" = $item.'Zip Code'
             "Home" = $item.Home
             "Mobile" = $item.Mobile
             "Fax" = $item.Fax
             "Job Title" = $item.'Job Title'
             "Department" = $item.Department
             "Company" = $item.Company
             "Status" = "Disabled" #this is static and should remain. Or set to whatever value you need for our application to disable the user.
         }
     }
 }
 $output | Export-CSV -Path "C:\temp\TestCSV\TEST_DISABLED_APP_USERS.CSV" -NoTypeInformation

Hope this helps with your query,

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