DOTNET object -> RunOnClient:Yes

Hi everyone,

After different upgrade for different customers, I've found an issue that makes me a little mess. I'll try to explain myself, and I hope you'll give me your thoughts.
Everything has to see with the development of the "Electronic VAT Information under SII", but I think that happens with every development with DOTNET objects.
I've made an upgrade for one customer to the NAV2017, and the development works perfectly, without changing any property of the DOTNET variables.
But instead, with another upgrade from other different client, doesn't happen the same.
In this case, I'm doing an upgrade to the NAV2018 version. When I try to run a development with DOTNET objects, I'm finding the error: "Cannot serialize DOTNET object". For one integration I've developed with external WebServices, I've solved this issue changing the RunOnClient property to "Yes", and I think that this issue, for the "Electronic VAT Information under SII", could be solved in the same way.
The thing is that I don't understand why this development run without changing anything in one server, and in this new one, I'm finding this issue.
Could be because of something in the server? Or the NAV installation? Any thoughts?

Thnak you all