A General SCSI Error message usually indicates that at least one of the two required settings in RasterPlus is incorrect.
To start, the rules of SCSI dictate that SCSI devices be connected to the computer and powered on before turning on or re-booting the computer.
If the first rule is followed and you still receive the error message click on Tools...SCSI Explorer. Make a note of the SCSI DEV ID for the printer and the SCSI Adapter ID directly above it.
Click on Edit...Default Queue Properties...General. Set the Connection to the SCSI DEV ID from the previous step.
Next click the Advanced Device Tab. Set the SCSI Adapter ID to the SCSI Adapter ID from the SCSI Explorer step.
Click OK. Click Tools...Save State. Now you should be able to successfully print.