Powershell determine the remote computer OS - windows

Question

I wrote a script to copy files to the "All Users" desktop or "Public Desktop"
However we have a mixed environment. Some people are using Windows XP and other people are using Windows 7.
$SOURCE = "I:\Path\To\Folder\*"
$DESTINATION7 = "c$\Users\Public\Desktop"
$DESTINATIONXP = "c$\Documents and Settings\All Users\Desktop"
$computerlist = Get-Content I:\Path\To\File\computer-list.csv
$results = #()
$filenotthere = #()
$filesremoved = #()
foreach ($computer in $computerlist) {
if((Test-Connection -Cn $computer -BufferSize 16 -Count 1 -ea 0 -quiet))
{
Write-Host "\\$computer\$DESTINATION\"
Copy-Item $SOURCE "\\$computer\$DESTINATION\" -Recurse -force
} else {
$details = #{
Date = get-date
ComputerName = $Computer
Destination = $Destination
}
$results += New-Object PSObject -Property $details
$results | export-csv -Path I:\Path\To\logs\offline.txt -NoTypeInformation -Append
}
}

Answer 1

DESTINATION is empty. Expanding on Keith's suggestion:
foreach ($computer in $computerlist) {
if((Test-Connection -Cn $computer -BufferSize 16 -Count 1 -ea 0 -quiet))
{
$OS = Get-WmiObject -Computer $computer -Class Win32_OperatingSystem
if($OS.caption -like '*Windows 7*'){
$DESTINATION = $DESTINATION7
}
if($OS.caption -like '*Windows XP*'){
$DESTINATION = $DESTINATIONXP
}
}
}
This could avoid the error you're getting also. empty $DESTINATION.

Answer 2

In your foreach loop through $computerlist you can grab the OS Caption for each computer by using WMI:
$OS = Get-WmiObject -Computer $computer -Class Win32_OperatingSystem
Ant then check the $OS
if($OS.caption -like '*Windows 7*'){
#Code here for Windows 7
}
#....

Answer 3

I had a slightly different goal...But thanks for the basics.
del C:\scripts\OS.csv
$computerlist = Get-Content c:\scripts\computerlist.csv
foreach ($computer in $computerlist) {
if((Test-Connection -Cn $computer -BufferSize 16 -Count 1 -ea 0 -quiet))
{
Get-WMIObject Win32_OperatingSystem -ComputerName $computer |
select-object CSName, Caption, CSDVersion, OSType, LastBootUpTime, ProductType| export-csv -Path C:\Scripts\OS.csv -NoTypeInformation -Append
}
}