A positional parameter cannot be found that accepts argument ' '.

I'm getting this error that I have been trying to resolve.  Need some help please.

PS H:\> C:\Errors-chk_exch4.ps1
A positional parameter cannot be found that accepts argument ' '.

At C:\Errors-chk_exch4.ps1:1 char:17

+     Get-WinEvent <<<<  -computername $server -filterhashtable $filter_system ` | where-object { ($_.LevelDisplayName -ne "Information") -and (($_.Id -ne 1111) -and ($_.ProviderName -ne "Microsoft-Windows-Term
inalServices-Printers")) -and (($_.Id -ne 6037) -and ($_.ProviderName -ne "LsaSrv")) }  ` | Select-Object LogName, MachineName, timeCreated, LevelDisplayName, ID, ProviderName, Message `
    + CategoryInfo          : InvalidArgument: (:) [Get-WinEvent], ParentContainsErrorRecordException
    + FullyQualifiedErrorId : PositionalParameterNotFound,Microsoft.PowerShell.Commands.GetWinEventCommand