Powershell script can't find URL - powershell

Question

I have a powershell that kicks off a workflow in SharePoint but my system is not allowing me to run it. The error I'm getting is as follows:
Get-SPWeb: Cannot find an SPWeb object with id or URL: xxx.com and site Url xxx.com
At C:\cert.ps1:1 char:17
+ $web = Get-SPWeb <<<< -Identity "xxx.com"
+ CategoryInfo : InvalidData (Microsoft.Share....SPCmdletGetWeb:SPCmdletGetWeb) [Get-SPWeb], SPCmdletPipeBindException
+ FullyQualifiedErrorId : Microsoft.SharePoint.Powershell.SPCmdletGetWeb
I tried adding Add-PSSnapin Microsoft.Sharepoint.Powershell but I the get an error saying its already been added.
Here's the script:
$web = Get-SPWeb -Identity "xxx.com"
$manager = $web.Site.WorkFlowManager
$list = $web.Lists["Certificate Tracking"]
$assoc = $list.WorkflowAssociations.GetAssociationByName("Certificate Notification","en-US")
$view = $list.Views["All Items"] #All Items
$items = $list.GetItems($view)
$data = $assoc.AssociationData
foreach ($item in $items) {
$wf = $manager.StartWorkFlow($item,$assoc,$data)
}
$web.Dispose()

Answer 1

The -Identity parameter for Get-SPWeb can be either a full or relative path, or a path with a wildcard * character. Additionally:
The identity param expects a valid URL in the form http://server_name or a relative path in the form of /SubSites/MySubSite.
Try this instead using the -Site param, which I think might be what you're looking for:
Get-SPWeb -Site http://sitename/sites/site1