First of all, make sure that you have installed the Sentinel drivers that came with FeatureCAM.   See the documentation in the README.WRI file in your C:\EZFM directory.   Following that, take a look at the following information.

The following article explains how to disable bi-directional communication on the parallel port:

Compatibility with New HP Printer Drivers and Sentinel-Protected Applications in Windows Environments
http://www.rainbow.com/tech/tech_notes/tn1056_b.htm

And here is a similiar article from HP:

http://www.hp.com/cgi-bin/cposupport/cspt/cds/dlvr.pl?lid=general&fid=bpd06455&pid=

The following document explains how to install and configure a second parallel port:

Printing to HP DeskJet Printers Under Win95 with Sentinel Keys
http://www.rainbow.com/tech/tech_notes/tn1065_a.htm

These links are on Rainbow Technologies' web site, and are beyond the control of Delcam USA.

One FeatureCAM customer reports experiencing the compatibility problems with his HP LaserJet 6MP.  He reports the following results:

• the 6MP driver causes crashes in both bi-directional and unidirectional mode
• the 5MP printer driver works and doesn't crash in both bi-directional and unidirectional mode

(The 6MP driver lets the printer print photographic quality B/W images, otherwise the two drivers seem to be the same.)

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