After I creat a new thread and post it happened the following error,but refresh the page, it recover ok

Error: My Posts is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: Requested value 'posts#24' was not found. ---> System.ArgumentException: Requested value 'posts#24' was not found. at System.Enum.Parse(Type enumType, String value, Boolean ignoreCase) at DotNetNuke.Modules.Forum.DNNForum..ctor() at ASP.desktopmodules_forum_forum_container_ascx.__BuildControlDNNForum() at ASP.desktopmodules_forum_forum_container_ascx.__BuildControlTree(desktopmodules_forum_forum_container_ascx __ctrl) at ASP.desktopmodules_forum_forum_container_ascx.FrameworkInitialize() at System.Web.UI.UserControl.InitializeAsUserControlInternal() at System.Web.UI.TemplateControl.LoadControl(IWebObjectFactory objectFactory, VirtualPath virtualPath, Type t, Object[] parameters) at System.Web.UI.TemplateControl.LoadControl(VirtualPath virtualPath) at System.Web.UI.TemplateControl.LoadControl(String virtualPath) at DotNetNuke.UI.Skins.Skin.InjectModule(Control objPane, ModuleInfo objModule, PortalSettings PortalSettings) --- End of inner exception stack trace ---

The URL is http://www.semisc.com/Default.aspx?tabid=56  could you help me to solve it .thanks

There is a problem in that version which causes this to occur when Friendly URL's are disabled on the install.