(Unknown error) - exit code -9 (0xfffffff7)
From BOINC Wiki
In general this error happens when the science application died before it got to the boinc_exit() code.
Known extra error codes around this error:
- CUDA cuInit: Unknown error
- Exception access violation.
- Exception caught: Worker application apparently died prematurely.
On Seti an error -9 means that the science application was stopped because it found too much noise in the task. See SETI@Home_Informational_message_-9_result_overflow for more information.