Exchange Script issue

PS C:\program files\microsoft\exchange server\scripts> ./install-antispamagents.ps1
Get-ItemProperty : Cannot find path 'HKLM:\SOFTWARE\Microsoft\Exchange\v8.0\Setup' because it does not exist.
At C:\program files\microsoft\exchange server\scripts\install-AntispamAgents.ps1:24 char:33
+ $InstallPath = (get-itemproperty <<<<  HKLM:\SOFTWARE\Microsoft\Exchange\v8.0\Setup).MSiInstallPath + "TransportRoles\agents\
"
    + CategoryInfo          : ObjectNotFound: (HKLM:\SOFTWARE\...ange\v8.0\Setup:String) [Get-ItemProperty], ItemNotFoundExcep
   tion
    + FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetItemPropertyCommand
                       
           At C:\program files\microsoft\exchange server\scripts\install-AntispamAgents.ps1:30 char:39
+ $transportserver = get-transportserver <<<<  -id $localservername
    + CategoryInfo          : ObjectNotFound: (get-transportserver:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException
 
Failed to find the transport server : MyExchangeLab