If your Blackboard Collaborate sessions aren't launching, and instead you are seeing Windows Media Player, Internet Explorer, or another application displaying code whenever you try to join a Collaborate session, you may need to re-associate .jnlp files to fix the issue.
Here's how to re-associate JNLP files with Java in Windows 8/8.1:
Click this link: http://j.mp/win8-associate-jnlp
We hope this information is helpful.
