Primary Master HDD error

When my pc boots I get “Pri master HDD error;sec slave drive-ATAPI incompatible” press F1 to continue, then it will continue to boot, then it searches for a boot record but finds none so I push reset and then it says “sec slave-ATAPI incompatible”,press F1 to resume”, then it will finanlly start and winxp will load and run okay. Could someone try to help me with this, I have tried everything I know!
Thanks,
Dave