good day every one ,

i am using dnn 3.1 and i entered as host user

when i am trying to change the site title from site setting in host user menu,

this error appear to me:

ModuleId: 369
ModuleDefId: 14
FriendlyName: Site Settings
ModuleControlSource: Admin/Portal/SiteSettings.ascx
AssemblyVersion: 03.00.13
Method: DotNetNuke.Modules.Admin.PortalManagement.SiteSettings.cmdUpdate_Click
FileName: C:\Inetpub\wwwroot\PixelsECS\admin\Portal\SiteSettings.ascx.vb
FileLineNumber: 857
FileColumnNumber: 17
PortalID: 1
PortalName: Welcome to QuQa Website
UserID: 1
UserName: host
ActiveTabID: 55
ActiveTabName: Site Settings
AbsoluteURL: /QuQa/Default.aspx
AbsoluteURLReferrer: http://10.16.0.13/quqa/Admin/SiteSettings/tabid/55/pid/1/portalid/1/Default.aspx
ExceptionGUID: 568e252f-f385-4659-877e-ac8764215cf5
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
InnerException: Object reference not set to an instance of an object.
Message: DotNetNuke.Services.Exceptions.ModuleLoadException: Object reference not set to an instance of an object. ---> System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Modules.Admin.PortalManagement.SiteSettings.cmdUpdate_Click(Object sender, EventArgs e) in C:\Inetpub\wwwroot\PixelsECS\admin\Portal\SiteSettings.ascx.vb:line 857 --- End of inner exception stack trace ---
StackTrace:
Source:
Server Name: SKHATEEB

whats the problem please??

please help me...