Ghost Column in Sharepoint by FieldRef deletion

Question

Let me explain my situation. I have some Document Libaries that derives from some content type some columns.

In some of these columns I have (by mistake) add two times the same columns with different names.

When I tried to delete it from PowerShell I user the command

SPList list = Web.Lists["NAME"];
SPContentType ct = list.ContentTypes["CTNAME"];
ct.FieldLinks.Delete("Descrizione Pratica");
ct.Update();

I believed that these will destroy only the column for the given content type but what I found now is what you can see in the picture:

I tried in many way to add the column back to my lists:

• Adding and removing it from Site Content Type

• Adding and removing it from List Content Type

• Adding and removing it from Fields of the list

But the list consider the field horribly wrong: I cannot insert data in that column, I can't se data stored... It's like the column does not exist..

Thank you very much!

Answer 1

I solved the problem in a very strange way.

This is the code:

$list = $Web.Lists["NAME"];
$ct = $list.ContentTypes["CTNAME"];
$ct.FieldLinks["Descrizione Pratica"];
$ct.Update($true);

Executing it from power shell and waiting a couple of seconds, the column started to work in the right way again..