Error when accessing the "Site Columns" from Site Admin (../_layouts/mngfield.aspx):

Error:

ErrorObject reference not set to an instance of an object. at Microsoft.SharePoint.ApplicationPages.FieldListRenderer.Render(HtmlTextWriter output) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at System.Web.UI.Control.Render(HtmlTextWriter writer) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) at System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at System.Web.UI.Control.Render(HtmlTextWriter writer) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) at System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) at Microsoft.SharePoint.WebControls.UnsecuredLayoutsPageBase.RenderChildren(HtmlTextWriter writer) at System.Web.UI.Page.Render(HtmlTextWriter writer) at Microsoft.SharePoint.WebControls.UnsecuredLayoutsPageBase.Render(HtmlTextWriter writer) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

Caused By:

Found it while deploying a solution for custom sites columns, which was generated by Visual Studio extension project.
(I haven't test it yet, but I guess that running either:
stsadm -o deploysolution -name "%PackageName%" -local -allowGacDeployment -url %TargetWebUrl%
or
stsadm -o activatefeature -id 772a7b6b-30ee-4041-83f7-7620dc74c142 -url %TargetSiteUrl%
will cause this problem)

It only appear when localhost is used for the TargetWebUrl and/or TargetSiteUrl.

Solution:

Uninstall the solution (setup -u in case you are using the solution files generated by the VS extension templates)
Use the fully qualified name of the web application (case sensitive?).

The operation could not be completed because the Web Part is not on this page

Error:


The operation could not be completed because the Web Part is not on this page.
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: Microsoft.SharePoint.WebPartPages.WebPartPageUserException: The operation could not be completed because the Web Part is not on this page.


Source Error:


An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.


Stack Trace:

[WebPartPageUserException: The operation could not be completed because the Web Part is not on this page.]
Microsoft.SharePoint.WebPartPages.SPWebPartManager.ThrowIfNotOnPage(WebPart webPart) +128
Microsoft.SharePoint.WebPartPages.SPWebPartManager.GetStorageKey(WebPart webPart) +36
Microsoft.SharePoint.WebControls.ViewIcon.get_Src() +172
Microsoft.SharePoint.WebControls.AlphaImage.Render(HtmlTextWriter output) +57
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +199
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +20
System.Web.UI.Control.Render(HtmlTextWriter writer) +7
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +199
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +20
System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) +59
System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) +68
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) +37
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +199
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +20
System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) +29
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +199
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +20
System.Web.UI.Control.Render(HtmlTextWriter writer) +7
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +199
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +20
System.Web.UI.Page.Render(HtmlTextWriter writer) +26
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2558


Cause by:

Web parts added declaratively (in the asp code) in a list's view (AllItems.aspx, Flat.apx, Threaded.aspx) or form (NewForm.aspx, DispForm.aspx or EditForm.aspx) which contains a SharePoint:ViewIcon control (responsible of drawing the list's image in the upper left corner of the page):

<SharePoint:ViewIcon Width="145" Height="54" runat="server" />


Example:
<WebPartPages:WebPartZone runat="server" D="WebPartZone1" >
<ZoneTemplate>
<Custom:MyWebPart runat="server" ID="MyWebPart1" />
</ZoneTemplate>
</WebPartPages:WebPartZone>



Solution:

1) Remove the SharePoint:ViewIcon from the page

or

2) Use C# code to inject the web parts in the page:

Example:

SPWeb web = SPContext.Current.Web;

SPLimitedWebPartManager wpManager = web.GetLimitedWebPartManager(web.Lists[listId].DefaultViewUrl, PersonalizationScope.Shared);

MyWebPart myWP = new MyWebPart();

myWP.ChromeType = PartChromeType.TitleAndBorder;

myWP.Title = "My Web Part";

wpManager.AddWebPart(myWP, "WebPartZone1", 0);