You might want to check out the updates for Debut.

http://poser.smithmicro.com/debut-updates.html

 

The last update says it works with Windows 8.0 and 8.1 and came out after the problems people were having with IE 11.

Poser 5, 6, 7, 8, Poser Pro 9 (2012), 10 (2014), 11, 12, 13