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Have you ever downloaded a ZIP file and realized too late that its contents are blocked by Windows? If you've already extracted it into a folder with existing files, it can be damn hard to figure out which ones need to be unblocked. Right-clicking every file and clicking the Unblock button is a lot of work. Luckily, PowerShell can unblock downloaded files in a whole folder for you.

Let's write a little PowerShell command to unblock files in a specific directory. Start by opening PowerShell and entering the following command.

gci  'c:Somefolder' | Unblock-File -WhatIf

The command above previews the unblock operation for the child items in the given directory. The WhatIf parameter doesn't make any changes; it shows you what the command would do. To actually unblock the files, remove that parameter.

gci 'c:Somefolder' | Unblock-File

As you may have noticed when using the WhatIf parameter, only files in this folder are included. What if you want to unblock files in subfolders too? You can do that by adding the Recurse parameter.

gci 'c:Somefolder' -Recurse | Unblock-File -WhatIf

I've used the WhatIf parameter again so I can check what the command is going to do. Once I'm happy with the preview, I can remove WhatIf and run the command against the files.

gci 'c:Somefolder' -Recurse | Unblock-File

Now you won't have to unblock each file by hand: run the command and you're ready to go. Bookmark this article to find the commands when you need them, and share it with your friends to make their lives a little easier too. Oh, and don't forget to have a look at the 'PowerShell Getting Started Guide' for more information on using PowerShell.