Error: "missing export PEGetWindowOptions"

Error "missing export PEGetWindowOptions" is being displayed when starting Atrex or when printing.

This error is caused by the presence of an old and incompatible version of the Crystal Reports print engine. 

Reinstall Atrex to overwrite the older version of the print engine with the version shipped with Atrex.

(Applies to Atrex 10 and older)