My restock script died on the first row of a Columbus store’s inventory CSV with “Cannot convert value to type System.Int32”. It means PowerShell tried to turn a value into a whole number and couldn’t. The quickest safe fix is to test the conversion first: In this tutorial, I’ll show you what causes cannot convert … Read more
PowerShell has two main error variables. $Error is an automatic list of every recent error in the session, newest first, and -ErrorVariable saves one command’s errors into a variable you name: In this tutorial, I’ll walk through the PowerShell error variables you’ll actually use: $Error, -ErrorVariable, $? and $LASTEXITCODE. You’ll also see where PowerShell 7 … Read more
To list printers using PowerShell, run Get-Printer. It returns every printer and printer connection installed on the computer, and you don’t need admin rights. Pipe it to Format-Table to pick the columns: In this post I’ll show you how to list printers using PowerShell with Get-Printer and Win32_Printer, read their status, find network printers, and … Read more
PowerShell Sort-Object puts objects in order by one or more property values. Pipe the objects in, name the property, and add -Descending if you want the largest values first: In this tutorial, I’ll show you how to use PowerShell Sort-Object with properties, numbers stored as text, dates, -Unique, -Top and hash tables. Every example below … Read more
To find the WWN number in Windows with PowerShell, run Get-InitiatorPort and filter for Fibre Channel ports. NodeAddress is the WWNN and PortAddress is the WWPN: Storage admins ask for the WWPN when they zone a switch or map LUNs to a server. Below I format the numbers the way SAN tools expect them, query … Read more
You want a script to show friendly status messages, maybe in green or red, without those messages leaking into the data it returns. That’s exactly the job Write-Host was built for. Quick answer: PowerShell Write-Host prints text straight to the console (the host), with optional -ForegroundColor, -BackgroundColor, -NoNewline and -Separator. It doesn’t send objects down … Read more
Get-ChildItem is the PowerShell cmdlet that lists what’s inside a location: the files and folders in a directory, the keys in a registry hive or the certificates in a store. Point it at a folder and you get the contents back as objects: I reach for it in almost every file script I write. Below … Read more
PowerShell Compare-Object takes two sets of objects and tells you which items exist on only one side. Give it a reference set and a difference set, and it returns the mismatches with an arrow showing where each one came from: I use it constantly for audits: two server lists, two folders, last month’s staff export … Read more
To read log files with PowerShell, use Get-Content for the lines and Select-String to find the ones that matter: The first line shows the newest 20 entries, and the second lists every error with its file name and line number. I tested each step below on sample Contoso logs in PowerShell 7 and Windows PowerShell … Read more
To find all files with a specific extension using PowerShell, run Get-ChildItem with -Filter, -Recurse and -File: That walks C:\Data and every subfolder and returns only .pdf files. Below, I test each variation on a small sample folder in PowerShell 7 and Windows PowerShell 5.1, including one 5.1 quirk that quietly adds the wrong files. … Read more