Check file size

I need to know a file's size. I tried with new FileInfo(filename).Length but it doesnt return me the right result. I also tried multiplying it by 1.024 but I still doesn't return the right value. I need to get the correct file size because I need to know it's size to send it thru my irc bot through Irc

(as side note the value is quite similar to the real one, but i need the REAL one)

Thanks in advance

Are you storing the returned value in a variable ? I worked on that and does return the exact file size though .

Are you sure it's .Length is not returning the correct file size? What are you comparing it against? It seems to work fine for me.