Scan for file and report back if it exists

Question

Hello,
I am new to scripting and trying to find a way to search for a supposed virus file named wsr[any two numbers]zt32.dll on a large group of computers. I'm not sure how or where to use Get-ChildItem -Path C:\Users -Filter ?zt32.dll -Recurse | export-csv
C:\scripts\output\test.csv in this script. 
The below script keeps erroring out when I try messing with the Test-Path options and I'm not sure where to use Get-ChildItem or whatever to get this working. Thanks
# Edit these variables to fit your enviroment
# Set file to be tested for, put everything after c:\
# “c:\Users\Default” is the example path
$filetofind = ‘wsr*zt32.dll ‘
# Hostnames TXT Location
$hostnamestxt = ‘C:\scripts\computernames.txt‘
# Destination file for Online Machines
$onlinetxt = ‘C:\scripts\output\Machines_with_file.txt‘
# Destination file for Offline Machines
$offlinetxt = ‘C:\scripts\output\Offline_Machines.txt‘
# Begin Executing Script – Do Not Edit Below This Line
$computers = get-content “$hostnamestxt”
write-host “———————————————-”
write-host “Scanning hostnames from $hostnamestxt…”
write-host “———————————————-”
foreach($computer in $computers)
ping -n 1 $computer >$null
if($lastexitcode -eq 0)
if(test-path “\\$computer\c:\users\* -include $filetofind”)
echo “$computer” | Out-File -Append “$onlinetxt”
write-host “File FOUND on $computer”
else
{write-host “File NOT found on $computer”}
else
echo “$computer” | Out-File -Append “$offlinetxt”
write-host “$computer is OFFLINE/DID NOT RESPOND TO PING”
write-host “———————————————-”
write-host “Script has completed please check output.”
write-host “Hosts with file output location – $onlinetxt”
write-host “Hosts that were unpingable output location – $offlinetxt”
write-host “———————————————-”

Answer 1

Although this works, it appears to be very slow. Also, the Offline machines are not getting logged. Is there a way to speed this up? I am reading about how gci is slow over UNC, but I'm going to have to research this more. Thanks
This makes the third time you have demanded someone custom build a solution for you.  You need to step back and think about what you are doing.  The solution was provided as you asked for it.  You lack of technical experience led you to ask
fot a now unworkable solution so you are asking for more free consulting and a new solution.
As Bill has pointed out this should be done with AV software as just finding the fiole will accomplish nothing.  If your system is infected you need to rake more aggressive steps and you should not be trying to write a scripted solution for this kind
of thing aunless you have the technical sjkills to understand what it is you are doing.
All remote scan methods are very slow.  To do a local scan requires emoting to be installed and that you know how to use it,  Once remoting is installed a single line will get you the file existence.  Adding an AsJob will get you concurrent
scanning.  You will need to learn how to use PowerShell and WMF remoting to proceed with this.  An AV scanner 2would be more valuable and it would protect you in the future.
Also as I posted before this is a very weak construct for file scanning on a network.
$g = get-childitem \\$computer\c$\user\*
-recurse -ErrorActionsilentlycontinue
|? {$_.name
-match "wsr[0-9][0-9]zt32.dll"}
The following will be much faster.
$g = get-childitem \\$computer\c$\user\* -Include
wsr*zt32.dll -recurse
-ErrorActionsilentlycontinue
¯\_(ツ)_/¯