add knx virtual devices to ETS

hello.I am new with knx.i wanted to train with ETS and virtual KNX.but my problem is that i cant add virtual devices into my project in ETS.There is no problem by adding devices from other companies but when adding virtual devices i see this error:

An internal error occurred.
Type 'Knx.Ets.Converter.ConverterEngine.Exceptions.UnsupportedNewerSchemaVersionException' in Assembly 'Knx.Ets.Converter.ConverterEngine, Version=4.0.1997.50261, Culture=neutral, PublicKeyToken=61439873ec5e1159' is not marked as serializable.

by the way, the connection between ETS and KV is ok . so what can I do to solve it?