The problem I'm having is removing items from an array.  We are auditing our computer accounts in AD every other week and if it falls into certain criteria, it gets deleted from AD, if no, we then crunch the array to compare it to a list of machines in our SCCM database. The problem lays with removing the items we delete from the main array before crunching it agains the SCCM numbers.  For example, here's the problem we are having:

$a = "a","b","c","d"
$b = @()
foreach($entry in $a){[string]($b = $b + $entry)}
$a += "e","f"
$c = @($a | where{($b) -notcontains $_})


Andrew

Sounds like a generic list is what you need:

$list1 = New-Object 'System.Collections.Generic.List[String]'
$list1.AddRange([String[]]("a", "b", "c", "d"))

$list2 = New-Object 'System.Collections.Generic.List[String]'
$list2.AddRange($list1)

$list1.AddRange([String[]]("e", "f"))

$list3 = New-Object 'System.Collections.Generic.List[String]'
$list3.AddRange($list2.FindAll({ $list2 -notcontains $_ }))

That will do the same as your original script. Can you go into a bit more detail about your situation? Or will that suffice?

For whatever reason, they call me Mr. Typo at work......seems there's a character or two off.  But the case here is my last line

$c = @($a | where{($b) -notcontains $_})

and if I use the "@" in front of the "($b)" it understands that it is an array item instead of formating it in a long single line.  The actual code from that portion of my script is(the dashes just show the start of each line  because they are long lines):

#Get list of computers that have not changed password in 45 days
-$over45 = @(foreach($entry in $computers){if (((new-timespan ([DateTime]::FromFileTime($Entry.properties.pwdlastset[0])) (get-date)).days) -ge 45){$entry.properties.cn}})
-$activedirectoryentries = @($activedirectoryentries| where-object {@($over45) -notcontains $_})

#find all machines older than 7 days with no machine authenticated to them
-$notauth = @(foreach($entry in $computers){if (($entry.properties.operatingsystem -eq $NULL) -and (((new-timespan ([DateTime]::FromFileTime($Entry.properties.pwdlastset[0])) (get-date)).days) -ge 7)){$entry.properties.cn}})
-$activedirectoryentries = @($activedirectoryentries| where-object {@($notauth) -notcontains $_})

Thanks for the help, I just needed to sit down with the technet article.....again.  I must admit I was a bit frustrated when he posted that link alone, I'd been there all morning trying to figure it out.  Why things work in shell and not ISE.....I'll not bother myself with that until I have more time to play with each environment.