These errors usually indicate an issue on the ATO side, i.e., 'GEN.FAULT.GENERALERRORINCORE An unhandled error occurred within Core Services'. Check the following:
Check your HandiTax version
Make sure you are on the latest version before retrying the lodgment.
Open HandiTax.
Select Help, About.
Select Software Updates.
Install the latest update if needed.
Retry the lodgment
If you are already on the latest version, try lodging the return again later. Temporary ATO service issues can cause this error.
Check the lodgment status
You can confirm whether the return was accepted outside of HandiTax.
Sign in to the Tax Agent Portal.
Locate the relevant return.
Check the lodgment status.
Contact the ATO to investigate
If the error continues, gather details from the Validation Report. To access the report:
Open the return in HandiTax.
Select Reports, then Report Navigator.
Open the Validation Report.
Locate the following details:
Transaction ID.
Message ID.
These identifiers are unique to your lodgment and help the ATO investigate the issue.
Request a second-tier consultant at the ATO and provide the Transaction ID and Message ID so they can identify the cause of the error.