Fix for a Recurring Meeting Workspace Error

A great time saving post on MS SharePoint Designer Team blog:
How to fix: Recurring Meeting Workspace error: ‘g_InstanceID’ is undefined

I ran into this problem after applying a custom master page to a meeting workspace, which was linked to a recurring event. Date selection on the left navigation stopped working if a custom master page was selected, but it worked fine when site master page was set to a standard SharePoint one.

Adding these two lines to a custom master page, mentioned in the blog post above, resolve the issue:

<%@Master language="C#"%>
<%@ Register Tagprefix="Meetings" Namespace="Microsoft.SharePoint.Meetings" Assembly="Microsoft.SharePoint, Version=, Culture=neutral, PublicKeyToken=71e9bce111e9429c"%>
<Meetings:PropertyBag runat="server"/>