I dod not know if you run your library on flash or air but you can try this.

You could try using the external library if you don't want to roll back to IE10

Edit Poser.ini to use external library ;
set  : LIBRARY_IS_AIR 1 in your Poser.ini file 

If you do roll back, here the download link to Microsoft to prevent IE 11 from being automatically reinstalled...

http://www.microsoft.com/en-us/download/details.aspx?id=40722

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