KB3142030

Blank Page For Skype For Business Web App

skypeforbusiness

I had an issue recently where remote clients couldn’t connect to Skype for Business online meetings – when clicking the link, all they saw in the browser was a blank page. The tab of the browser showed ‘Skype for Business Web App’ but the page area had nothing.

This didn’t seem to affect all external clients (internal was fine), when I tested on Windows Server 2012 R2 from home it worked fine. Windows 7 however was affected, and I’m not sure on Windows 8, 8.1 or 10.

This technet post mentions it breaks ‘Conferencing Functionality and PowerPoint Presentations’ as well as ‘ White Boarding, polling’ which was caused by KB3142030. Hoping that was our problem, I uninstalled the update and rebooted – but no luck.

The next check was around .NET framework 4.6.1 which is unsupported on Exchange and Skype for Business Servers (Lync too!) but we didn’t have that installed, due to using the suggested registry setting in the linked article to block the install.

After an evening of troubleshooting and rebooting servers and firewalls that didn’t help, our support found the problem for us – a misconfigured load balancer, that had an incorrect IP for one of the front-end Skype for Business servers. Updating the IP immediately resolved the issue.

Looking back on it, that explains why I had some clients work and not others – it just appeared to be in a pattern that was OS related due to the luck of round robin routing on a load balancer!

Due to the way Skype for Business handles the web requests, by first hitting an edge server then an internal front end server, you may have multiple load balancers in the way and get partial page loading.

Another lesson learnt!