To unblock a download on Windows, you need to remove the "Mark of the Web" tag that Windows automatically adds to files from the internet. The quickest way to unblock a download on Windows is to right-click the file, select Properties, check the Unblock box on the General tab, and click Apply.
Why Windows blocked your download and how to unblock it
When you download a file from the internet, Windows uses a security feature called Attachment Manager to add "Mark of the Web" (MotW) metadata to the file. This tag tells Windows where the file came from, which can trigger security warnings. Your file isn't necessarily dangerous, Windows is just being cautious because it came from outside your computer. Before you override any block, always verify you used a legitimate download link to avoid malicious look‑alike sites, and if you're hosting files yourself, you can make a link automatically download a file so visitors get the same MotW treatment. The goal is to help you understand that you can safely override this block when you trust the source.
How to unblock a download in File Explorer
This is the primary method to remove the block from a single file. Follow these steps:
- Locate the downloaded file in File Explorer.
- Right-click the file and select Properties.
- Go to the General tab.
- In the Security section at the bottom, check the Unblock box.
- Click Apply, then OK.
After completing these steps, the Mark of the Web is removed, and Windows will no longer block the file. You can now open or run it without warnings.
How to keep a blocked download in Microsoft Edge
If you use Microsoft Edge and it blocks a download, you can override the block directly from the browser. This action also removes the Mark of the Web from the file. In the download tray, find the blocked download, click the three dots (or similar menu icon) next to it, and select Keep. Edge will then allow the download and unblock the file automatically.
How Windows Defender SmartScreen decides what to block
Microsoft Defender SmartScreen is a built-in Windows feature that protects against phishing sites, malware, and potentially malicious downloads by checking the reputation of websites and files. SmartScreen evaluates both the publisher's reputation (based on digital signatures) and the file's hash reputation. Files without an established reputation may trigger warnings. This is why a brand-new or rarely downloaded file might be blocked even if it's perfectly safe. Apps downloaded from the Microsoft Store are re-signed by Microsoft and have full reputation, meaning they will not trigger SmartScreen download warnings.
How to verify a publisher's digital signature
Before you unblock a file, you can manually check its digital signature to build trust. A digital signature confirms the file's origin and that it hasn't been tampered with. Here's how:
- Right-click the file and select Properties.
- Go to the Digital Signatures tab (if it exists).
- Select the signature from the list and click Details.
- Check that the signature is valid and the publisher is someone you recognize and trust.
If the signature is valid and from a reputable publisher, you can proceed with unblocking the file with more confidence. This step is especially useful for software installers or executable files.
A last resort for advanced users: the group policy setting
For advanced users on Windows Pro or higher, the Group Policy setting "Do not preserve zone information in file attachments" can prevent the Mark of the Web from being added to downloaded files entirely. This should be used with extreme caution because it disables the feature globally, meaning Windows will no longer tag any downloaded file with its internet origin. This removes a primary layer of defense against online threats and is not recommended for typical users. Only consider this if you fully understand the security implications and have other protections in place.
