Oscam conversation

I use the same oscam version in 800SE & 800.

It depends on the type of processor (and this depends on the type of chipset architecture). It also depends a bit on the type of Enigma you use. If you use the original Enigma in Dreambox devices, then in the case of the newer DM800, this is probably the OE 2.5 core. In case of DM500 I don't know (OE 2.0 core?). For example, if you use the OE Alliance Group (OpenATV, OpenPLi, etc.) Enigma, then there should be an OE 2.0 core. So the problem could be the OE version of the core in Enigma.

https://en.wikipedia.org/wiki/Dreambox#Dreambox_models

Dreambox 800HD and 800HD-SE have almost similar chipset architecture and the same processor (mips32el). So the same Oscam should work (either an installation package or a binary file).