Get-VulnerabilityRSSFeed_InvokeWebRequest

Try 
        {
        # Conditional logic to determine if the switch to retrieve information from the Microsoft Security Bulletin RSS feed has been specified.
        If ($Microsoft)
            {  
            # Retrieves content from the Microsoft Security Bulletin RSS feed. 
            [xml]$WebRequest = Invoke-WebRequest -Uri https://technet.microsoft.com/en-us/security/rss/bulletin 
            # Selects objects retrieved where the published date is greater or equal to the timespan speficied.
            $Items = $WebRequest.rss.channel.item | Where-Object {$_.pubDate -ge "$Date"}
            # Performs action on each item returned to calculate expressions for output object. 
            ForEach ($Item in $Items)
                {
                "" | Select-Object @{N="Title";E={(($Item.title -split ": ")[1] -split " - ")[0]}},@{N="PublishedDate";E={Get-Date ($Item.pubDate) -Format d}},@{N="Source";E={"Microsoft Security Bulletin"}},
                @{N="Description";E={($Item.InnerText -split "Summary: ")[1]}}, @{N="Link";E={$Item.link}},@{N="Severity";E={(($Item.title -split " - ") -split ":")[1]}}
                } # ForEach
            } # If 
        # Conditional logic to determine if the switch to retrieve information from the National Vulnerability RSS feed has been specified.
        If ($NVD)
            { 
            # Retrieves content from the National Vulnerability Database RSS Feed.
            [xml]$WebRequest = Invoke-WebRequest -Uri  https://nvd.nist.gov/download/nvd-rss.xml            
            # Selects objects retrieved where the published date is greater or equal to the timespan speficied.
            $Items = $WebRequest.rdf.item | Where-Object {$_.Date -ge "$Date"} 
            # Performs action on each item returned to calculate expressions for output object. 
            ForEach ($Item in $Items)
                {
                # Conditional logic to determine if the item returned matches one of the keyword values. 
                If ($Item.InnerText -match $Keywords)
                    {
                    "" | Select-Object @{N="Title";E={$Item.title}},@{N="PublishedDate";E={Get-Date ($Item.Date) -Format d}},@{N="Source";E={"National Vulnerability Database "}},@{N="Description";E={$Item.description}},@{N="Link";E={$Item.link}},
                    @{N="Severity";E={""}}
                    } # If 
               } # ForEach 
            } # If 
        } # Try