Here is how to factory reset an HP Jetdirect 170X external print server.
- Unplug the power to the Jetdirect.
- Press and hold the “Test” button while plugging the power back in for 5 seconds.
- The Jetdirect should be reset now and is configured by default to obtain an IP address automatically.
I have embedded the PDF manual for the Jetdirect 170x Installation and Configuration manual.
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00758101/c00758101.pdf