Running WSS 3.0. We are attempting to change (add-to) the list of allowable items in a Choice Field. We can create a new choice field, but when adding a new value, we get the error page: Method not found: 'Void Microsoft.SharePoint.SPField.ClearDefaultValueAndDefaultFormula()' Turning on web.config debugging gives: Method not found: 'Void Microsoft.SharePoint.SPField.ClearDefaultValueAndDefaultFormula()' at Microsoft.SharePoint.ApplicationPages.ManageFieldPage.UpdateFieldPage.UpdateFieldWithPropertiesFromXml(SPField fld, String strXml) at Microsoft.SharePoint.ApplicationPages.ManageFieldPage.ProcessList() at Microsoft.SharePoint.ApplicationPages.ManageFieldPage.onLoad(EventArgs e) at System.Web.UI.Control.LoadRecursive() at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) Neither Google or Bing had anything useful to say. Also tried the diagnostic logging, but nothing in there that was useful.

Hi there. If the WSS log files doesn't have any additional useful information, and you don't have any customization on the list, you maybe will have to update to the latest SP/CU, if this is a known issue. (If you receive a "method not found" for a core SharePoint assembly, you may also have some aspx pages that are out of sync with the installed assemblies, i.e. install the latest SP/Cu to cure this.) Regards, Magnus My blog: InsomniacGeek.com

We traced it down to a specific web part. During it's install we need to do a "stsadm -o copyappbincontent". When we uninstalled the WP, the columns behave correctly. The WP only adds a new ASPX page. Very strange behavior.

Hi. Well, make sure that this customization doesn't install an old Microsoft.SharePoint.dll assembly. (Or any other core assembly) Regards, MagnusMy blog: InsomniacGeek.com

Marked as answer because it seems to be the most logical.

A co-developer actually found the answer. Our WSP solution was deploying an older version of Microsoft.SharePoint.ApplicationPages.dll to the GAC. Removed that and things worked fine.