.wav recognised as .cda in win xp

My old pc running win98se, recognises the audio tracks written on a cdr that I wrote myself as .wav files.
My new pc running winXP will only recognise the tracks as .cda.
Why is this?
I have to run them through a conversion programme on the XP machine before I can play about with them in Wave Editor.
Is there a setting in XP that I’m not aware of needing to be changed? I’m at a loss to know what is different between the 2 systems.
Thanks for your help.