You join an online meeting by using Lync Room System
You use the Lync Room System whiteboard feature for interactive collaboration with in-room or remote meeting attendees
You have added up to 1000 drawing annotations by using the Lync Room System whiteboard feature
In this scenario, the Lync Room System whiteboard's drawing feature becomes unresponsive.
The Lync Server 2013 Web Conferencing Service has a limitation of 1000 drawing annotations per whiteboard session. This limitation has the same effect on the Lync Room System client, the Lync 2013 client and the Lync Web App 2013 client.
The workarounds for this issue are described in below:
Erase any unneeded drawing annotations from the Lync Room System whiteboard. This step will allow the addition of more drawing annotations to the Lync Room System whiteboard.
Add another whiteboard to the meeting using the Lync Room System client. This will allow the addition of up to 1000 more drawing annotation to the meeting.