The column cannot be altered via the application server. Ask your DBA to issue the following statement against the database, then re-attempt the operation.

Namespace:  FileNet.Api.Exception
Assembly:  FileNet.Api (in FileNet.Api.dll)

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Visual Basic (Declaration)
Public Shared ReadOnly DB_UNABLE_TO_ALTER_COLUMN As ExceptionCode
C#
public static readonly ExceptionCode DB_UNABLE_TO_ALTER_COLUMN
Visual C++
public:
static initonly ExceptionCode^ DB_UNABLE_TO_ALTER_COLUMN
JavaScript
FileNet.Api.Exception.ExceptionCode.dB_UNABLE_TO_ALTER_COLUMN

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