This morning, someone asked me to look into a site-compatibility problem on a HTML5 demo site. When loading the site into IE9 and IE10, the F12 Developer Tools’ Script Debugger showed the following error: Now, obviously, IE does support getElementsByTagName, and I confirmed that the...

Inside Internet Explorer’s Tools > Internet Options > Advanced dialog, there’s an option named Enable Integrated Windows Authentication : This preference is stored using a REG_DWORD named EnableNegotiate inside HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings...

I recently encountered a blog that isn’t looking right in IE9: The site renders just fine in other browsers, and when the page is put into Compatibility View by ticking the icon in the address bar: What’s going on here? It’s clear that a stylesheet isn’t...

As we explore network performance on the “real-world web”, one bad pattern in particular keeps recurring, and it’s not something that our many IE9 Networking Performance Improvements alone will resolve. The bad pattern is the use of Connection: close semantics for HTTPS connections...

Just a quick little advertisement: On the heels of the successful Fiddler session at PDC last fall , I'll be hosting a "mini-session" on Fiddler at the MIX 2010 conference next Wednesday morning. I hope to meet some of you there! Update 3/23/2010: The video from my talk is now live...