Trouble deleting acl using RemoveAccessRule

I’m new to playing around with acl’s in the file system. I can add rights but I can’t figure out how to remove acl’s. Here is the code I have.

$FolderPath = "\\filedirectory"
$acl = get-acl $FolderPath

#I use this to remove all acl's that are not inherited.  When I ouptut $acl.access it does remove them (in this case it just removes one security group with my test)
$ACL.access | Where-Object {$_.isinherited -eq $false}  | %{ $ACL.RemoveAccessRule($_) }

#I get the error when I set-acl.  
set-acl -path $Folderpath -aclobject $ACL

The error I gets is as follows:

set-acl : AclObject At C:\Users\admin.isilver1\Documents\saveacl\restore_acl.ps1:405 char:9

  •     set-acl -path $Folderpath -aclobject $ACL
  •     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    • CategoryInfo : InvalidArgument: (System.Collections.Hashtable:Hashtable) [Set-Acl], ArgumentException
    • FullyQualifiedErrorId : SetAcl_AclObject,Microsoft.PowerShell.Commands.SetAclCommand

I have scurried the web for information with no luck. Any help would be great.

I’ve finally got it figured out. I knew posting it here would help. It turns out I use $acl variable for something else. After I changed the name it fixed the problem.