Opening Planning webforms (11.1.2.3.500) very slow using IE 9

Hello,

I'm facing an issue when opening large webforms (EPM 11.1.2.3.500) in IE 9 .

Using IE 8, it takes an average of 30 seconds.

Using Firefox 24.6.0 ESR, it takes an average of 12 seconds.

Using IE 9, it takes an average of 390 seconds.

I've applied the recommendations for IE browsers.

Are there any other settings which might be specific to IE 9 ?

Thanks for your help.

Regards,

Andy