If I make a change in design-mode to a form that has a DropDownList or an UltracomboEditor, I'm seeing a strange error.  I'm trying to add a button -- the change I'm making to the form shouldn't affect the dropdown at all, but it does.  It looks like when the .resx file is getting recreated, it somehow adds the wrong value.  After the change, the form won't compile, and VS won't even let me reopen the form.  Full text of the error is below.  In the .Resx File:

<data name="ValueListItem24.DataValue" mimetype="application/x-microsoft.net.object.binary.base64">
  <value>
        AAEAAAD/////AQAAAAAAAAAEAQAAAB9TeXN0ZW0uVW5pdHlTZXJpYWxpemF0aW9uSG9sZGVyAwAAAARE
        YXRhCVVuaXR5VHlwZQxBc3NlbWJseU5hbWUBAAEICgIAAAAGAgAAAAAL
  </value>
</data>

becomes 

<data name="ValueListItem24.DataValue" mimetype="application/x-microsoft.net.object.binary.base64">

    <value>
        AAEAAAD/////AQAAAAAAAAAEAQAAAA1TeXN0ZW0uREJOdWxsAwAAAAREYXRhCVVuaXR5VHlwZQxBc3Nl
        bWJseU5hbWUBAAEICgIAAAAGAgAAAAAL
</value>

Error      138         TargetInvocationException: Type  in the data at line 1046, position 5, cannot be loaded because it threw the following exception during construction: Only one DBNull instance may exist, and calls to DBNull deserialization methods are not allowed.

   at System.Resources.ResXResourceReader.ParseXml(XmlTextReader reader)

   at System.Resources.ResXResourceReader.EnsureResData()

   at System.Resources.ResXResourceReader.GetEnumerator()

   at Microsoft.Build.Tasks.ProcessResourceFiles.ReadResources(ReaderInfo readerInfo, IResourceReader reader, String fileName)

   at Microsoft.Build.Tasks.ProcessResourceFiles.ReadResources(String filename, Boolean shouldUseSourcePath)

   at Microsoft.Build.Tasks.ProcessResourceFiles.ProcessFile(String inFile, String outFileOrDir)

XmlException: Type  in the data at line 1046, position 5, cannot be loaded because it threw the following exception during construction: Only one DBNull instance may exist, and calls to DBNull deserialization methods are not allowed. Line 1046, position 5.

NotSupportedException: Only one DBNull instance may exist, and calls to DBNull deserialization methods are not allowed.

   at System.DBNull..ctor(SerializationInfo info, StreamingContext context)

Thanks,

    Brad Larsen

    Stratis Business Systems, Inc.