I have developed an excel spreadsheet using Excel XP and have used various vba code in th spreadsheet. A user using Excel 97 complains that the spreadsheet did not function properly.

Are there differences in the type of code you can use between the versions of excel? Can something be done to remedy the difference

One specific instance of failure the user mentioned was "undefined replace function". Does this function not exist in excel 97

Is there somewhere I can find out all the differences between the various versions? Could it be there is something wrong with this users pc and its not the worksheet?