If you’re having problems launching your legacy apps while running Internet Explorer 11, it’s most likely because Internet Explorer no longer starts apps that use managed browser hosting controls, like in .NET Framework 1.1 and 2.0.
To turn managed browser hosting controls back on
For x86 systems or for 32-bit processes on x64 systems: Go to the
HKLM\SOFTWARE\MICROSOFT\.NETFrameworkregistry key and change the EnableIEHosting value to 1.
For x64 systems or for 64-bit processes on x64 systems: Go to the
HKLM\SOFTWARE\Wow6432Node\MICROSOFT\.NETFrameworkregistry key and change the EnableIEHosting value to 1.
For more information, see the Web Applications section of the Application Compatibility in the .NET Framework 4.5 page.