This operation is not available for read only field 'Template'.(SBL-DAT-00402)

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Siebel
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This operation is not available for read only field 'Template'.(SBL-DAT-00402)
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OK 
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This is one of most common error of every siebel implementation.Usually this error is followed by :

Cannot set a value for field %1 because it is not active. (SBL-EXL-00147)

The first thing which we tend to do is to set the force active property of field to true and recompile and end up getting this error in logs:

(omextlng.cpp (4682)) SBL-DAT-00402: This operation is not available for read only field 'Template'.

In my case I tried several things but couldn't pass through this error, until I noticed provided whereIndicator in New Record Command. Once I made this change both the error were resolved.

.....
bc.ExecuteQuery(ForwardOnly);
var ap = bo.GetBusComp("Activity Plan");
ap.InvokeMethod("SetAdminMode", "Y");
ap.ClearToQuery();
ap.ExecuteQuery(ForwardOnly);
ap.NewRecord(NewAfter);
ap.SetFieldValue("Template","AP1");
ap.WriteRecord();
...

Using where indicator is only one of the reason for SBL-DAT-00402 error. Please share your experiences if this helps.