A riddle: office '03 and the Diamond

[intangible04]

I'm trying to not save excel spreadsheets on my Diamond as office 2007 format as I only have '03 on my lappy. So, I had a friend convert my excel spreadsheet to '03 format, put it back on my Diamond tried exiting and it will not let me save it as a .xls. I've already downloaded the patch they have that should convert 07 to 03 but of course it doesn't work and when it does it's not effectively. Have at it. I can't stand office 07 and refuse to upgrade to it let alone pay for it right now so don't take the easy way out and say to upgrade because that's simply not an option.