Warning: The retired, out-of-support Internet Explorer 11 desktop application has been permanently disabled through a Microsoft Edge update on certain versions of Windows 10. For more information, see Internet Explorer 11 desktop app retirement FAQ.
Consider the following scenario. You turn on the SmartScreen Filter in Windows Internet Explorer 9 and then try to download a file type that is supported by SmartScreen Application Reputation. In this scenario, the following warning message unexpectedly appears on the download notification bar in Internet Explorer 9:
This type of file could harm your computer
The SmartScreen Application Reputation service checks the reputation of a file. Therefore, you should not see the generic "This type of file could harm your computer" warning message when you try to download a file type is supported by SmartScreen Application Reputation. This issue occurs because the file name extension in the URL differs from the actual file name extension. (The actual file name extension is specified by the "content-disposition: attachment" HTML header.) Because of the different file name extensions, the warning message is displayed incorrectly.
Security update information
To resolve this problem, install the most recent cumulative security update for Windows Internet Explorer. To do this, visit the following Microsoft website:
http://update.microsoft.com For more technical information about the most recent cumulative security update for Internet Explorer, visit the following Microsoft website:
http://www.microsoft.com/technet/security/current.aspxNote This update was first included in security update 2530548 (MS11-050). For more information, click the following article number to view the article in the Microsoft Knowledge Base:
2530548 MS11-050: Cumulative security update for Internet Explorer: June 14, 2011