You can set the general print options for double-sided printing and envelopes for all letters via the "Settings" field. 

Afterwards, it is always possible to adjust the individual print options in the preview window. 

1. Click on the drop-down button next to your login name and then on Settings.

 

2. In the menu under Print you can make the general settings.

  

3. Finish and close the settings via Save.

The option "Use CIB pdf brewer print settings for single- or double-sided printing" causes the print settings for single- or double-sided printing to be transferred by the application from which the printout is made. This means that the print options set in CIB fairBrief simplex or duplex printing will be ignored. Example: If this option is activated, simplex printing is selected in CIB fairBrief and duplex printing is set in Microsoft Word, the document will be printed on both sides, because the option is taken from Microsoft Word.