Please confirm the information below first:
1.Please use 12.9-12.11 non-Microsoft Store iTunes.
2.Please make sure iTunes is signed in, iTunes authorized the computer.
3.The Apple ID you used to sign in iTunes is not locked.
4.You can play the original iTunes audiobook on the computer.
5.Please convert on 64-bit computer.
If above are confirmed, please restart Leawo and re-try to see if the same problem persists.
If yes, please contact us with the following information:
1.The iTunes version you are using.
2.The audiobook names you are converting.
3.Please click top right Settings>Help in Leawo Prof. DRM to submit Bug Report.