About Arbortext Styler > Document Preview and Publishing > Logic for Print/Preview Engine Selection
  
Logic for Print/Preview Engine Selection
A summary of the logic governing print engine selection for publishing print or PDF from Arbortext Editor or in Arbortext Publishing Engine:
The default print engine is PTC ALD.
If the printengineoverride1 option has a value of app2, fosi or xslfo, that will be used as the print engine for the publishing action.
If the printengineoverride option has a value of no, the publishing action will use the print engine setting configured for the stylesheet3.
1
The printengineoverride option is set in Arbortext Editor via a set command. See set printengineoverride in the Arbortext Command Language Reference for further information.
2
If PTC ALD is not available, an error message is displayed. You can choose whether to continue publishing using FOSI.
PTC ALD will not be available if you do not have Arbortext Styler or Arbortext Publishing Engine installed in your PTC Arbortext environment.
3
A stylesheet’s print engine property is set in the Print/PDF tab of the Stylesheet Properties dialog box in Arbortext Styler.
The effective print engine for your environment will be displayed for reference:
1. In publishing dialog boxes: a Print engine field appears in the Print and Publish to PDF File dialog boxes.
2. In the session information in Arbortext Editor: select the Help > Session menu option. Navigate to the Document tab and refer to the Effective print engine entry. See Session dialog box for further information.
* 
The FOSI and XSL-FO print engines are on sustained support and do not receive enhancements or maintenance fixes. PTC ALD is the recommended engine for print/PDF output.