Exporting Managed Properties in SharePoint 2010 via a PowerShell script

I’m running this script I found on technet.
Why am I receiving the following error below?

Export Managed/Crawled Properties from Enterprise Search https://gallery.technet.microsoft.com/office/Export-ManagedCrawled-7548d31b

PS C:\> .\Export-SpSearchManagedProperties.ps1
Get-SPEnterpriseSearchMetadataManagedProperty : SearchApplication Search Service not found.
At C:\Staging\Export-SpSearchManagedProperties.ps1:14 char:67
+ $ManagedPropreties = Get-SPEnterpriseSearchMetadataManagedProperty <<<<  -SearchApplication $SearchServiceApp
+ CategoryInfo          : InvalidData: (Microsoft.Offic...ManagedProperty:GetSearchMetadataManagedProperty) [Get-SPEnterpris...ManagedProperty], KeyNotFoundException
+ FullyQualifiedErrorId : Microsoft.Office.Server.Search.Cmdlet.GetSearchMetadataManagedProperty

You cannot call a method on a null-valued expression.

At C:\Staging\Export-SpSearchManagedProperties.ps1:28 char:32
+     $Mappings = $MP.GetMappings <<<< ()
    + CategoryInfo          : InvalidOperation: (GetMappings:String) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

You cannot call a method on a null-valued expression.
At C:\Staging\Export-SpSearchManagedProperties.ps1:33 char:29
+             if ($CP.Contains <<<< (":") -eq $true){
+ CategoryInfo          : InvalidOperation: (Contains:String) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull

PS C:\>

============================================================

My Environment – Windows Server 2008 R2 Datacenter 64-bit

$PSVersionTable Name Value PSVersion 2.0

$host Name : ConsoleHost Version : 2.0 UI : System.Management.Automation.Internal.Host.InternalHostUserInterface

Get-SPEnterpriseSearchServiceInstance -local TypeName : SharePoint Server Search Description : Index content and serve search queries Role : None Status : Online