The issue of .NET 4.0 Web pages not rendering properly for specific versions of Internet Explorer is a repeat of the recent inability of the ASP.NET engine to detect IE 10 . Frankly, I’m surprised that this continues to be a problem and that Microsoft has not come out with a long-term solution other than urging developers to upgrade to ASP.NET 4.5 or face constantly having to deal with detection problems.
In particular ASP.NET 2.0 and ASP.NET 4.0 are in constant danger of serving non-functional Web pages to new versions of Internet Explorer. I do not have sites running ASP.NET 2.0, but have seen this issue happen with .NET 4.0 sites.
I faced this issue previously with the release of IE10. Sadly, while the patch worked nicely for the first release versions of IE10, the recent patch for IE11 does not work at all, and it is looking doubtful that Microsoft will be releasing a working patch for Windows Server 2003 since they plan on discontinuing support for it in 2015 (specifically in: 07/14/2015).
As you may have noticed, I mentioned above that the MS patch worked for the release versions of IE10. That’s because the patch that worked for IE10 did so only to a point. Midway through 2013 Microsoft released a patch for a zero-day exploit that somehow altered the signature of IE to an extent where the .NET 4 engine was no longer able to identify IE10 correctly, and I was back to trying to get the .NET engine to properly serve Web pages. Continue reading “ASP.NET Doesn’t Detect IE11”