Hi,
I would like to give more info about issue.
I use child theme of twenty twelve theme, and wp 3.5.1 ( also tried 3.6)
I try to upload files at IE8/9/10 at both compatibility mode and non-compatibility mode, but it doesn't upload file.
Media upload works properly, but file upload at your plugin doesn't work.
In compatibility mode, IE gave below description;
System.InvalidCastException: Error 0x17E0. Hata ayıklama kaynak dizeleri kullanılamıyor. Bkz. http://go.microsoft.com/fwlink/?linkid=106663&Version=5.1.20513.0&File=mscorrc.dll&Key=0x17E0
konum System.Windows.Browser.ManagedObjectInfo.Invoke(ManagedObject obj, InvokeType invokeType, String memberName, ScriptParam[] args)
konum System.Windows.Hosting.ManagedHost.InvokeScriptableMember(IntPtr pHandle, Int32 nMemberID, Int32 nInvokeType, Int32 nArgCount, ScriptParam[] pArgs, ScriptParam& pResult, ExceptionInfo& pExcepInfo)
Satır: 1
char: 4182
Kod: 0
URI: http://…….com/wp-includes/js/plupload/plupload.silverlight.js?ver=1.5.5
I hope, this info assists you to find a solution.
Regards