## Specify output file to write data to
$FILE = "${Env:UserProfile}\Desktop\InstalledSoftware.csv"

## Clear content of output file
If ( Test-Path $FILE ) { Clear-Content -Path $FILE -Force }

## Write the headers to the output file
Write-LineToFile -Path $FILE -Line "Name,Publisher,Version,InstallDate,EstimatedSize(MB),UninstallString,ModifyPath"

ForEach ( $item in $(Get-ChildItem -Path 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall','HKLM:\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall') ) {
    If ( Test-ItemProperty -Path $item.PSPath -Name DisplayName ) {
        $DisplayName = Get-ItemPropertyValue -Path $item.PSPath -Name DisplayName
        $DisplayName = $DisplayName -replace ",", " "
    } Else { $DisplayName = "" }

    If ( Test-ItemProperty -Path $item.PSPath -Name DisplayVersion ) {
        $DisplayVersion = Get-ItemPropertyValue -Path $item.PSPath -Name DisplayVersion
        $DisplayVersion = $DisplayVersion -replace ",", " "
    } Else { $DisplayVersion = "" }

    If ( Test-ItemProperty -Path $item.PSPath -Name EstimatedSize ) {
        $EstimatedSize = Get-ItemPropertyValue -Path $item.PSPath -Name EstimatedSize
        $EstimatedSize = $EstimatedSize -replace ",", " "
        $size = [int]$EstimatedSize
        $size = [Math]::Ceiling($size / 1024)
        $EstimatedSize = [string]$size
    } Else { $EstimatedSize = "" }

    If ( Test-ItemProperty -Path $item.PSPath -Name InstallDate ) {
        $InstallDate = Get-ItemPropertyValue -Path $item.PSPath -Name InstallDate
        $InstallDate = $InstallDate -replace ",", " "
    } Else { $InstallDate = "" }

    If ( Test-ItemProperty -Path $item.PSPath -Name Publisher ) {
        $Publisher = Get-ItemPropertyValue -Path $item.PSPath -Name Publisher
        $Publisher = $Publisher -replace ",", " "
    } Else { $Publisher = "" }

    If ( Test-ItemProperty -Path $item.PSPath -Name UninstallString ) {
        $UninstallString = Get-ItemPropertyValue -Path $item.PSPath -Name UninstallString
        $UninstallString = $UninstallString -replace ",", " "
    } Else { $UninstallString = "" }

    If ( Test-ItemProperty -Path $item.PSPath -Name ModifyPath ) {
        $ModifyPath = Get-ItemPropertyValue -Path $item.PSPath -Name ModifyPath
        $ModifyPath = $ModifyPath -replace ",", " "
    } Else { $ModifyPath = "" }

    ## Write installed software to output file only if it has a name, otherwise discard
    If ( $DisplayName -ne "" ) {
        $content = "${DisplayName},${Publisher},${DisplayVersion},${InstallDate},${EstimatedSize},${UninstallString},${ModifyPath}"
        Write-LineToFile -Path $FILE -Line $content
    }
}