Extracting es0 file

Hi,
I’m a newbie to the forum. Pardon me if this is too elementary a question. I would like to update my 5005 firmware. I went to their download site and plugged in my serial number and then followed the prompt to download the zipped file. I extracted it to a single es0 file. My impression is that there should have been multiple files. I then went back to their site and tried the same thing but this time I downloadeded the .exe version and extracted it (again to a single es0 file) with winrar. I went ahead and burned it to a cd and then popped it into the drive but it didn’t recognize. My serial number is 0102-1840-0090-8203 (103-010D). Can someone please point me to the correct file or let me know what I am doing wrong?

Thanks in Advance
Meredith Meagher