If you want AcuServer to output error messages to an error log, specify the -e option when starting AcuServer with acuserve -start. On Windows, you can also specify the error log file using the AcuServer Control Panel (ACP).
If -e is not specified in UNIX, acuserve will attempt to direct error output to /dev/console.
In Windows, acuserve will attempt to direct error output to a file named acuserve.err in the Windows NT/2000 system directory (typically c:\winnt\system32). If these directories cannot be opened, acuserve will attempt to append to a file named acuserve.err in the current directory. If that file doesn't exist, or the file append fails, acuserve will print the message acuserve: can't open error output file to standard output, and acuserve will terminate.
See Starting and Stopping acuserve for more information on the -e option.