Can't modify anything on my Deathadder Chroma Mouse

Hi everybody, Wanted to ask if anyone knows what to do so I can modify my DPI for my mouse. When I open Synapse it just says that I need synapse 2.0 to be able to modify my mouse. Problem is that I have tried installing MANY times synapse 2.0 and even tried 3 but nothing. All I want is to be able to modify my DPI, don't really care for any macros or lighting. When trying to contact support they just say that my mouse is outside of warranty, which I find to be an absolute joke of customer service. I'm not asking for a replacement or anything of that sort, but I expected a minimum of respect and decency to at least help me out with a clear software problem. Thank you beforehand to anyone that could help me out.