AdoMD.NET connection string

hi, I've got slightly big problem.
In AdoMD.NET at ADOMDConnection class I can't set
connection string, anything I put in it, the exception jump out.
Even if I want add connection string via constructor.

Connection string I am using: "Provider=MSOLAP;Data Source=localhost;Initial Catalog=FoodMart"

I have installed Analysis Services.

I even tried but a word like "hi" or empty string "" into connection string,
it happens every time. Is there bug on ADOMD.net side or I am doing
something wrong?