A customer of mine was adding modules and building out pagesand went to lunch.

He then came back and a bunch of modules were missing from several of his pages.  On these same pages he tried to add a new HTML module to the page and when the page refreshed, there was not HTML module onthe page.

I have seen this happen in the past when the same module with same module id gets added to the same page twice ,it can throw some errors.

When I look in the event viewer here is what I see.

All of these errors are showing the same error just withdifferent page names.

AssemblyVersion: 04.09.05

PortalID: -1
PortalName: 
UserID: -1
UserName: 
ActiveTabID: -1
ActiveTabName: 
RawURL: /MyECGCourse/Chapter10/tabid/138/Default.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer: http://domainname.comMyECGCourse/Chap...
UserAgent: Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider,DotNetNuke.SqlDataProvider
ExceptionGUID: b6832ee0-9172-47b0-a0c9-981b33346877
InnerException: An item with the same key has already been added.
FileName: 
FileLineNumber: 0
FileColumnNumber: 0
Method: System.ThrowHelper.ThrowArgumentException
StackTrace: 
Message: System.ArgumentException: An item with the same key has already beenadded. at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value,Boolean add) atDotNetNuke.Entities.Modules.ModuleController.FillModuleInfoDictionary(IDataReaderdr)
Source: 
Server Name: server3