This error occurs when an invalid system description is specified. TDL has a fixed set of system definition types like Events, Formulae, Form Keys, Menu Keys, TDL Names, UDF, and Variables. %s : System definition type
Correct the definition type to a valid type.
Example
[System: UDFs]
In the above code, a system definition called UDFs is specified which is not a valid system definition type. Hence the message error T0011: The system description type 'UDFs' is invalid. appears.
The code is corrected by changing the definition name to UDF.
[System: UDF]