forking process failed (Connection refused: AJAX API)

Trying to start a scan. Immediately after trying to start, the error message “Missing lock file.” appears.

Of course, the troubleshooting page they have has nothing about this error, but if you search this forum, the error is widespread. No idea why it wouldn’t be included in the troubleshooting docs.

Anyways, click into the log file:

30-Oct-23 00:28:45 ERROR Fatal error: forking process failed (Connection refused: AJAX API). Aborting
30-Oct-23 00:28:45 INFO Cancelling scanning process ()
30-Oct-23 00:28:47 INFO Cancelling scanning process (nscan_check_status: response != success)