How to prevent Windows 10 from blocking downloaded files

By stating that the file has an unknown origin (and therefore may not be safe), Windows can block it from being opened. To avoid any problems this OS blocks all content that could be potentially harmful. The conditional, however, in this case, is rather exhaustive: many times what has been downloaded is actually safe but so is not reported by Windows.

How then? In this article we will address the problem, trying to tell you how to prevent Windows 10 from blocking downloaded files.

Prevent Windows 10 from blocking downloaded files with Attachment Manager

In Windows 10, there is a security feature called Attachments management. When the operating system refuses to open downloaded files, this is the utility that intervenes.

This is a defensive function, useful for preventing the opening of fraudulent email attachments. In the event of even the slightest sign of danger, Attachment Manager intervenes and Windows 10 offers you the fateful blocking window.

How does this feature work? Mostly it classifies downloaded files, based on the file extension and file name. While it is true that reading an email is not inherently dangerous, attachments are notoriously one of the riskiest factors of malware.

Windows Attachment Manager uses the API IAttachmentExecute to analyze the file type and, consequently, to determine the most appropriate action to take. When you download files and save them to disk, Windows adds specific metadata to them and is considered attachments. The operating system, therefore, can evaluate the file just added to the hard disk through metadata, file name, and origin of the same: if Windows detects that the file comes from unknown sources, it prevents you from opening it.

How to open a locked file and how to prevent Windows 10 from blocking downloads

If you want to manually open a locked file, right-click on it and select Property. In the card General, click Unlock, then on Apply, and then on OK: everything is easy unless you are dealing with a large number of files. If you frequently download files from the Internet or receive files as email attachments, you may want to completely prevent your PC from locking your files.

To prevent Windows 10 from locking files, you need to prevent it from adding metadata to them once they are downloaded. You can do this by configuring Attachment Manager manually using the procedures we will list below.

How to configure Attachment Handling via the registry

To take action via the registry editor, you need to follow these steps:

• Press the Windows key + R to open the registry editor;
• Type Regedit and click Enter;
• Now a User Account Control prompt will appear. When this message appears, click the button Yup to continue;
• Once the editor is open, look for the key HKEY_CURRENT_USER – Microsoft – Windows – CurrentVersion – Policies – Attachments.

If the Attachments key is missing from the Policies key, you will need to create it. To do this, right-click the key CurrentVersion, click on New, then on Key. This will create a new key, which you should then call Policies. If you find that the key Attachments are already there, you can skip to the next step.

At this point you can proceed:

• Right-click the Attachments key, then click New and then select Values ​​DWORD (32 bit);
• You will be asked to name this newly created DWORD value. Call him SaveZoneInformation and click Enter;
• Finally, to disable Attachment Handling in Windows 10, double-click the newly created SaveZoneInformation value and change the value data to 1;
• Click OK to finish.

After completing these steps, close the registry editor and restart your computer to apply the changes. From here on, any downloaded file will no longer have the aforementioned metadata, and opening it should no longer cause problems.

Please note: in doing so, however, you will need to pay particular attention to the files you download. In fact, it should not be forgotten that Attachment Management was born as a defense formula and, once this function is disabled, our operating system is theoretically more vulnerable.

If you want to go back and enable Attachment Manager again, you can do so by accessing the previously created key. From here, on the right-hand side, double-click the SaveZoneInformation value and change the value data to 3.

Configure Attachment Handling using the Policy Editor

The Local Group Policy Editor is only available in editions Windows 10 Enterprise, Education is Pro. Consequently, this method is not applicable if you own Windows 10 Home. In that case, the only way to prevent Windows 10 from blocking downloaded files is to act through the system logs.

Those who have these versions, on the other hand, can follow the procedure listed here:

• To start, press the key Windows + R, type gpedit.msc, and click Enter to open the Local Group Policy Editor;
• Go to User Configuration – Administrative Templates – Windows Components – Attachment Management;
• In the right pane of Attachment Manager, double-click the policy Do not keep zone information in file attachments;
• Select the option to not keep zone information in file attachments in Group Policy Editor.

A window will appear in which you can choose whether or not the attachment manager should keep information about where the files are coming from. So, click Qualified to allow Attachment Manager not to keep information on where the files are coming from. This will ensure that Windows doesn’t lock your files every time you open them – click the button Apply to save the changes, then click OK to confirm.

Once the editor window is closed, restart the operating system for the changes made to take effect.