In fact, ActiveX can enable hackers to take full control of a PC! That's obviously a problem from a security standpoint. An ActiveX control can enable a rogue program to delete, modify, transmit, or do anything else to data discovered on the computer. The problem is that ActiveX allows a program to make unrestricted changes to the user's computer.
ActiveX controls may be thought of as plugins or addons for the IE browser. Typically, an ActiveX control is downloaded through Internet Explorer the first time it is needed that is, the first time content that requires the ActiveX control is encountered by Internet Explorer.
Microsoft uses ActiveX controls to install security updates via Microsoft Update. Some online games require the use of ActiveX controls. For example, an ActiveX control developed by Adobe Systems enables Internet Explorer to display Flash, Acrobat, and other types of multimedia content. In Internet Explorer, ActiveX serves a function similar to Java, but without Java's security safeguards.Īn ActiveX control (sometimes called an add-on) is a set of instructions that, when installed on a computer, enable specific actions.
Although it is often referred to as a programming or scripting language, ActiveX is more accurately defined as a set of rules established by Microsoft that govern how applications written in other languages share information. ActiveX is a Microsoft programming framework that was introduced to Windows and Internet Explorer in 1996. An example of an API that can end up changing the Tab Thread's Input Queue is SetWindowLong.Let's start with a definition. Setting the HangRecovery value to 0 disables this feature setting it to 1 enables it.Īvoid calling AttachThreadInput or other APIs that can potentially result in changing the owner for the Tab window, since those APIs affect the Tab Thread's Input Queue. The Hang Resistance feature is enabled by default in Internet Explorer 9. There are several ways to work around this problem:Īvoid making long running blocking calls or performing any synchronous work on a UI Thread that can potentially interfere with the thread's Message Pump.Ĭreate the following Registry Key Value to disable the Hang Resistance feature: HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\
The fix for this issue is available in Internet Explorer Cumulative Update MS11-099 (KB 2618444) or any Internet Explorer Cumulative Update onwards. Microsoft has confirmed that this is a problem in Internet Explorer 9 related to how the Hang Resistance feature works.
The problem happens because the Tab Window is detached from the Frame Window's Input Queue. This issue can affect any UI element on the page that is able to receive focus. The controls may appear disabled, or the focus may end up in the address bar when a user clicks on the page to try to get focus. Original product version: Internet Explorer 9 Original KB number: 2600156 SymptomsĪ web page or ActiveX control hosted in a web page can stop receiving focus intermittently when being viewed using Internet Explorer 9. This article provides information on resolving webpage issues that can't get focus in Internet Explorer 9. The same IE11 apps and sites you use today can open in Microsoft Edge with Internet Explorer mode. The Internet Explorer 11 desktop application will be retired and go out of support on J(for a list of what's in scope, see the FAQ).