is there a way I can remove the key, value from the states store when de-serialization exception comes in the init() method while iterating the state store?
That’s a little tricky… you can sure sure catch the exception and swallow it, to avoid crashing…
For cleaning it up, it might be required to put some workarounds in place – if you change the store key/value types to <byte[]/byte[]> you could side-step the deserialization, and try to deserialize “manually” in your use code, ie, create the deserializer explicitly in your own code and call deserialize(...) yourself – and if it fails, you can call delete() passing in the key as byte[].