I’ve had a “bug” raised by a client using IE9 Browser Mode with Document Mode IE7 standards set (why it is set to this I don’t know see attached image) 
This is causing a styling error obviously and the client has requested I fix the error. I’m nearly 100% sure there is nothing I can do to target this sort of a set up and fix the problem. I’m using Modernizr to target the different browsers. I would like a robust answer to bring back to the client as to why this is a scenario I can’t fix or if I am wrong and there is something I could do to rectify this then I would appreciate the help.
Thanks.
I don’t believe there will be much you can do about this. There are meta tags that enforce the standards but if the user opens up their developer tools and manually selects the settings then it’s not really a problem worth looking into.