00381: Error=18, TCB(10)=-5, when opening an LPT device

Title:

Error=18, TCB(10)=-5, when opening an LPT device

Description:

This error can be caused by HP’s printer status software. The software monitors the LPT port, informing the user when paper is out, toner is low, etc. The software blocks direct access to the port. 

This has also been seen when the printer is attached to a Win2003 Server being opened on Win98 using an alias line incorporating UNC thusly: 
        ALIAS LP //server/printer “” CR 
The printer had the powersave mode enabled and was “shutdown” so the error occurred on the OPEN. 

Resolution:

HP suggests disabling the status software. On some newer printers, there is a de-install program that must be run.