How to Unblock a File in Windows 10
The Attachment Manager is included in Windows to help protect your PC from unsafe attachments that you might receive with an e-mail message and from unsafe files that you might save from the Internet. If the Attachment Manager identifies an attachment that might be unsafe, the Attachment Manager prevents (blocks) you from opening the file, or it warns you before you open the file.
It uses the IAttachmentExecute application programming interface (API) to find the file type, to find the file association. When one of these applications saves a downloaded file on a disk formatted with NTFS, then it updates the metadata for the file with the zone it was downloaded from. The metadata is saved as an Alternate Data Stream (ADS). If you wish to unblock a downloaded file, you can do so by right-clicking it, selecting Properties and clicking on Unblock.
The following determine whether you are prevented from opening the file or whether you are warned before you open the file:
- The type of program that you are using.
- The file type that you are downloading or trying to open
- The security settings of the Web content zone that you are downloading the file from.
- Internet
- Local intranet
- Trusted sites
- Restricted sites
The Attachment Manager classifies files that you receive or that you download based on the file type and the file name extension. Attachment Manager classifies files types as high risk, medium risk, and low risk.
- High Risk – If the attachment is in the list of high risk file types and is from the restricted zone, Windows blocks the user from accessing the file. If the file is from the Internet zone, Windows prompts the user with a Windows Security Warning: Windows found that this file is potentially harmful. To help protect your computer, Windows has blocked access to this file.
- Moderate Risk – If the attachment is in the list of moderate risk file types and is from the restricted or Internet zone, Windows prompts the user with a warning: "The publisher could not be verified. Are you sure you want to run this software?".
- Low Risk – If the attachment is in the list of low risk file types, Windows will not prompt the user before accessing the file, regardless of the file’s zone information.
The Open File - Security Warning prompt is a security measure that will ask for your permission before opening a file on your PC that came from an unknown source such as the Internet or another PC.
Windows SmartScreen helps keep your PC safer by warning you before running unrecognized apps and files downloaded from the Internet.
Open File - Security Warning and Windows SmartScreen automatically blocks these types of apps and files until you unblock them.
Starting with Windows 10 build 17639, if you have Windows Defender Application Guard turned on, blocked files will have a icon overlay on the file's icon to indicate the file is currently blocked.
This tutorial will show you different ways on how to unblock files that are blocked by Open File - Security Warning and Windows SmartScreen in Windows 10.
Be sure to only unblock files that you trust to avoid compromising the security of your PC.
Contents
- Option One: Unblock File in Properties
- Option Two: Unblock File in Open File - Security Warning
- Option Three: Unblock App or File in Windows Defender SmartScreen
- Option Four: Unblock a Single File in PowerShell
- Option Five: Unblock All Files in a Folder in PowerShell
- Option Six: Unblock Files in a Folder and every Subfolder in PowerShell
- Option Seven: Unblock File(s) using Context Menu
EXAMPLE: Blocked file when Windows Defender Application Guard is turned on
1 Right click or press and hold on the blocked file, and click/tap on Properties.
2 Click/tap on the General tab, check the Unblock box at the bottom, and click/tap on OK. (see screenshot below)
If you do not see a Unblock checkbox, then the file is not blocked.
3 If prompted, click/tap on Continue, and click/tap on click/tap on Yes (if administrator) or enter password of administrator (if standard user) for UAC prompt. (see screenshot below)
You will only be prompted if the file is in a location that your user account does not have access rights to by default.
1 Open or run the blocked file to trigger the Open File - Security Warning prompt.
2 In the Open File - Security Warning prompt, uncheck the Always ask before opening this file box, and click/tap on the Open or Run button. (see screenshots below)
3 If prompted by UAC, click/tap on Yes (if administrator) or enter password of administrator (if standard user).
You will only be prompted if the file is in a location that your user account does not have access rights to by default.
1 Open or run the blocked app or file to trigger the Windows SmartScreen.
2 Click/tap on the More info link. (see screenshot below)
3 Click/tap on the Run anyway button. (see screenshot below)
1 Open Windows PowerShell or an elevated Windows PowerShell depending on if your user account has access rights to where the blocked file is located.
2 Type the command below into PowerShell, and press Enter. (see screenshot below)
unblock-file -path "full path of blocked file"
Substitute full path of blocked file in the command above with the actual full path of the blocked file (with file extension) that you want to unblock.
For example:unblock-file -path "C:\Users\Brink\Desktop\Example.reg"
1 Open Windows PowerShell or an elevated Windows PowerShell depending on if your user account has access rights to where the folder containing the blocked file(s) is located.
2 Type the command you want to use below into PowerShell, and press Enter. (see screenshot below)
(without confirmation prompt)
get-childitem "full path of folder" | unblock-file
OR
(with confirmation prompt)
get-childitem "full path of folder" | unblock-file -confirm
Substitute full path of folder in the command above with the actual full path of the folder that contains the blocked file(s) you want to unblock.
For example:
get-childitem "C:\Users\Brink\Desktop" | unblock-file
OR
get-childitem "C:\Users\Brink\Desktop" | unblock-file -confirm
1 Open Windows PowerShell or an elevated Windows PowerShell depending on if your user account has access rights to where the folder containing the blocked file(s) is located.
2 Type the command you want to use below into PowerShell, and press Enter.
(without confirmation prompt)
get-childitem "full path of folder" -recurse | unblock-file
OR
(with confirmation prompt)
get-childitem "full path of folder" -recurse | unblock-file -confirm
Substitute full path of folder in the command above with the actual full path of the folder that contains the blocked file(s) you want to unblock.
For example:
get-childitem "C:\Users\Brink\Desktop" -recurse | unblock-file
OR
get-childitem "C:\Users\Brink\Desktop" -recurse| unblock-file -confirm
That's it,
Shawn Brink
Related Tutorials
- How to Add Unblock File Context Menu in Windows 10
- How to Disable Downloaded Files from being Blocked in Windows
- How to Change Windows SmartScreen Settings in Windows 10
- How to Bypass "This app has been blocked for your protection" in Windows 10