instruccions to recover lost data and sheets of a 2003 excel file.

In 2008 I found what seemed an unreported bug in excel 2007 In those days I was still using office 2003, I switched to excel 2007 and I found that when I opened a file created in excel 2003 I lost 2 worksheets (default 2 and 3 sheets) and in the file just remained the worksheet numbered as sheet 1; first I panic searched in google but couldn’t find anything so what I did was reinstall the old version of excel and Voila, the lost pages came back, it was not a problem of the sheets been hidden, in other window or minimized, no they had gone. Based in this supposed bug, a few months after this founding I reinstalled the 2003 version of excel and I “hide” Some important information in the sheets number 2 and 3 assuming that it would only be visible using that version of excel. The years passed and I throw away the old software versions I used, now I need the information and it has not been possible to recover, I have tried everything, even buy a rig as the one I had back then and try to reinstall all the excel 2003 versions I found, I have tried combining with all the versions windows vista and windows xp; of course I have also tried newer versions and double check is not a problem of hidden sheets somehow. I also have tried some “tools” to recover corrupted files and so but nothing seems to work, do not remember the specific version I had but I remember it was not original. I need the help of an expert, I can´t give the file away but I offer that If the help makes me recover the data I could give a reward. Thank you.