We all know about the bug in .net 2 and .net4 browser definition files that prevents it from recognising certain browser types (namely IE10)
There are hotfixes available for this, but not via Microsoft update – you have to request them and the link is emailed to you.
This is an easy enough process and can be requested from:
http://support.microsoft.com/kb/2600100 - for Win7 SP1/Windows Server 2008 R2 SP1, Windows Vista/Server 2008, Windows XP/Server 2003
http://support.microsoft.com/kb/2608565 - for Win7/Windows Server 2008 R2 RTM
Or, if you run Server 2008 R2 SP1, here are the direct download links to save time: