Alfons,
We are also having this problem after upgrading to BI 4.1 SP6. Not all but some of our users have reported it in IE 11. Changing to emulate IE 10 seems to resolve the problem. We have over 200 users and our infrastructure team is pushing out IE 11 to them all.
Can someone please advise if we need to have our users go back to IE 10 or if this will be fixed soon.
Thanks,
Faith