Add the following section to the web.config:

<configuration>
   <system.web>
       <compilation debug="true"/>
   </system.web>
</configuration>

And report the exact error you get.

Ah ...

Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

Line 11:                 int forumId = umbraco.presentation.nodeFactory.Node.GetCurrent().Id;
Line 12:                 umbraco.presentation.nodeFactory.Node n = new umbraco.presentation.nodeFactory.Node(forumId);
Line 13:                 int _currentMember = umbraco.cms.businesslogic.member.Member.GetCurrentMember().Id;
Line 14:
Line 15:                 if (_currentMember > 0 && n != null && umbraco.cms.businesslogic.web.Access.HasAccces(n.Id, _currentMember))
 

Source File: d:\Intranet\sites\UKPHA2\www\masterpages\NewTopic.master    Line: 13

Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.]
   ASP.masterpages_newtopic_master.btCreateTopic_Click(Object sender, EventArgs e) in d:\Intranet\sites\UKPHA2\www\masterpages\NewTopic.master:13
   System.Web.UI.WebControls.Button.OnClick(EventArgs e) +111
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +110
   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565
 

The website uses a "custom" membership provider (i.e. not the standard Umbraco one) ... I assume that's the reason? uForum recognises that I am logged on OK though. Where is the "problem" - uForum or the custom provider?

The problem is the compatibility, not one or the other. But i would tinker with the custom membership provider to provide the right methods and results to uForum.

This is the class that is returning null:

        public static Member GetCurrentMember()
        {
            try
            {
                int _currentMemberId = CurrentMemberId();
                if (_currentMemberId != 0)
                {
                    // return member from cache
                    Member m = GetMemberFromCache(_currentMemberId);
                    if (m == null)
                        m = new Member(_currentMemberId);

                    if (HttpContext.Current.User.Identity.IsAuthenticated || (m.UniqueId == new Guid(getCookieValue("umbracoMemberGuid")) &&
                       m.LoginName == getCookieValue("umbracoMemberLogin")))
                        return m;

                    return null;
                }
                else
                    return null;
            }
            catch
            {
                return null;
            }
        }

This looks for the cookie that Umbraco own membership provider sets. Your provider does not do this, so you need to change the source of uForum to use another way of identifying the current user. Both when posting new topics, but probably also when displaying topics, to display the user name.

OK - so I assume that I could update the membership provider to create the same cookie ("umbracoMemberLogin")? I'd rather do as few changes to uForum as possible.

yep would be my preferred solution too.

Hey guys,

i'm less of an ASP.NET user than I should be, so can you tell me where I should go to make the edit that Gordon suggests (update the membership providor cookie)

Thanks very much!!
Dave

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