• Start Visual Studio in safe mode using:  Start->Run->devenv /safemode
• In the Toolbox “Choose items”, accept any error message the appear
• Restart Visual Studio as per normal and the problem should be fixed.

SPException “Cannot change the lookup list of the lookup field.”

Once a lookup field (SPFieldLookup) has had it’s LookupList and LookupWebId set you can’t change them.

There is a good reason for this if your lookup field is used in multiple lists or already has data entered, you would effectively break the referential integrity of the data. So what I’m showing here as a work-around to this error message should only be used if you are *sure* no lists reference the lookup column or no lists have any data using this column

Okay with the health warning out of the way the work-around is simply to update the Schema property to overwrite the intervalues for List & WebId

I created a handy extension method for dealing with the string manipulation:

Usage:

SPFieldLookup field = (SPFieldLookup)site.RootWeb.Fields[MyId];
field.UpdateLookupReferences(newWeb, newList);

Implementation:

public static class SPFieldLookupExtensions
{
    public static void UpdateLookupReferences(this SPFieldLookup lookupField, SPWeb web, SPList list)
    {
        if (string.IsNullOrEmpty(lookupField.LookupList))
        {
            lookupField.LookupWebId = web.ID;
            lookupField.LookupList = list.ID.ToString();
        }
        else
        {
            lookupField.SchemaXml =
                lookupField.SchemaXml
                    .ReplaceXmlAttributeValue("List", list.ID.ToString())
                    .ReplaceXmlAttributeValue("WebId", web.ID.ToString());
        }

        lookupField.Update(true);
    }
}

public static string ReplaceXmlAttributeValue(this string xml, string attributeName, string value)
{
    if (string.IsNullOrEmpty(xml))
    {
        throw new ArgumentNullException("xml");
    }

    if (string.IsNullOrEmpty(value))
    {
        throw new ArgumentNullException("value");
    }

    int indexOfAttributeName = xml.IndexOf(attributeName, StringComparison.CurrentCultureIgnoreCase);
    if (indexOfAttributeName == -1)
    {
        throw new ArgumentOutOfRangeException("attributeName", string.Format("Attribute {0} not found in source xml", attributeName));
    }

    int indexOfAttibuteValueBegin = xml.IndexOf('"', indexOfAttributeName);
    int indexOfAttributeValueEnd = xml.IndexOf('"', indexOfAttibuteValueBegin + 1);

    return xml.Substring(0, indexOfAttibuteValueBegin + 1) + value + xml.Substring(indexOfAttributeValueEnd);
}

Engine RunWorkflow: System.Workflow.ComponentModel.Compiler.WorkflowValidationFailedException: The workflow failed validation.     at System.Workflow.Runtime.WorkflowDefinitionDispenser.ValidateDefinition(Activity root, Boolean isNewType, ITypeProvider typeProvider)     at System.Workflow.Runtime.WorkflowDefinitionDispenser.LoadRootActivity(Type workflowType, Boolean createDefinition, Boolean initForRuntime)     at System.Workflow.Runtime.WorkflowDefinitionDispenser.GetRootActivity(Type workflowType, Boolean createNew, Boolean initForRuntime)     at System.Workflow.Runtime.WorkflowRuntime.InitializeExecutor(Guid instanceId, CreationContext context, WorkflowExecutor executor, WorkflowInstance workflowInstance)     at System.Workflow.Runtime.WorkflowRuntime.Load(Guid key, CreationContext context, WorkflowInstance workflowInstance)     at System.Workflow.Runtime.WorkflowRuntime.GetWorkflowExecutor(Guid instanceId, CreationContext context)     at System.Workflow.Runtime.WorkflowRuntime.InternalCreateWorkflow(CreationContext context, Guid instanceId)     at System.Workflow.Runtime.WorkflowRuntime.CreateWorkflow(Type workflowType, Dictionary`2 namedArgumentValues, Guid instanceId)     at Microsoft.SharePoint.Workflow.SPWinOeHostServices.Send(SPWinOeWorkflow winoeworkflow, SPWorkflowEvent e)     at Microsoft.SharePoint.Workflow.SPWinOeEngine.RunWorkflow(Guid trackingId, SPWorkflowHostService host, SPWorkflow workflow, Collection`1 events, TimeSpan timeOut)

If your workflow uses validation rules it might be:

1) A problem with your validation rules, restart Visual Studio re-compile are any errors picked up?

2) Missing the .net 3.5 workflow targets in your project file see: http://blog.hhebnes.no/post/WSPBuilder-Workflow-Failed-On-Start.aspx

1. Domain name is correct
2. If using custom sources, try creating a new custom source and deleting the old one

Solution

This worked for me, your mileage, may and probably will vary.

It was necessary for me to un-gac the workflow project, then the custom activities could be added to the design surface as expected.

The DataSourceID of ‘TopNavigationMenu’ must be the ID of a control of type IHierarchicalDataSource.  A control with ID ‘topSiteMap’ could not be found.   at System.Web.UI.WebControls.HierarchicalDataBoundControl.GetDataSource()
   at System.Web.UI.WebControls.HierarchicalDataBoundControl.ConnectToHierarchicalDataSource()
   at System.Web.UI.WebControls.HierarchicalDataBoundControl.OnLoad(EventArgs e)
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

Troubleshoot issues with Windows SharePoint Services.

Server Error in ‘/’ Application.

---

Parser Error

Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.
Parser Error Message: This page has encountered a critical error. Contact your system administrator if this problem persists.
Source Error:

Line 1:  <%@ Page Inherits="Microsoft.SharePoint.Publishing.TemplateRedirectionPage,Microsoft.SharePoint.Publishing,

Version=12.0.0.0,Culture=neutral,PublicKeyToken=71e9bce111e9429c" %> 

<%@ Reference VirtualPath="~TemplatePageUrl" %> 

<%@ Reference VirtualPath="~masterurl/custom.master" %>
Line 2:  <html xmlns:mso="urn:schemas-microsoft-com:office:office" 

xmlns:msdt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882"><head>
Line 3:  <!--[if gte mso 9]><xml>

Source File: /Pages/Default.aspx    Line: 1

Event log error message

Safe mode did not start successfully. Could not load file or assembly ‘MyCompany, Version=1.0.0.0, Culture=neutral, PublicKeyToken=XXXXXXXX’ or one of its dependencies. The system cannot find the file specified.

Solution

In my case the error message from the event log was spot on. I had accidentally removed a MyCompany assembly from the GAC.

Other errors can also cause the same problem, whilst debugging this issue I came across another blog post that might be of interest: http://www.dotnetmafia.com/blogs/dotnettipoftheday/archive/2008/09/24/safe-mode-did-not-start-successfully-request-failed.aspx

To check if a feature is installed examine the feature definitions collection on the SPFarm object, below are a couple of little extension methods that demonstrate this concept.

/// <summary>
/// Defines extensions made to the <see cref="SPWeb"/> class
/// </summary>
[CLSCompliant(false)]
public static class SPWebExtensions
{
    public static bool IsFeatureActivated(this SPWeb web, Guid featureId)
    {
        return web.Features[featureId] != null;
    }

    public static bool IsFeatureInstalled(this SPWeb web, Guid featureId)
    {
        SPFeatureDefinition featureDefinition = SPFarm.Local.FeatureDefinitions[featureId];
        if (featureDefinition == null)
        {
            return false;
        }

        if (featureDefinition.Scope != SPFeatureScope.Web)
        {
            throw new GeneralApplicationException(
                string.Format("Feature with the ID {0} was installed but is not scoped at the web level.", featureId));
        }

        return true;
    }
}

Once I installed the InfoPath client application  with .Net Programmability Support, see below, the targets file was installed to the MSBuild directory.

if (!web.IsRootWeb && !web.HasUniqueRoleDefinitions)
{
      web.RoleDefinitions.BreakInheritance(true, false);
}

Turned out the there were subtle errors in my onet.xml. In particular I was referencing some document templates using an incorrect path:

<Project Title="$Resources:onet_TeamWebSite;" xmlns="http://schemas.microsoft.com/sharepoint/"  Revision="2" ListDir="$Resources:core,lists_Folder;" xmlns:ows="Microsoft SharePoint">
  ...
  <DocumentTemplates>
    <DocumentTemplate Path="INCORRECTPATH" Name=""