Instructions for Installing the ExtendUnits6 package for Mathematica Version 6.0. You should have downloaded Units6.zip - The package and documentation. Find your personal Mathematica\Applications folder, by evaluating $UserBaseDirectory or $BaseDirectory in Mathematica. You should find an Applications folder there. Unzip the Units6.zip files into the Application folder (not into the Units6 folder. That folder will be automatically created.) At the conclusion your should have the structure: Mathematica\Applications \ExtendUnits6 (package file and tutorial) \Documentation \English (Help Documentation files and notebooks) In the Documentation Center you will find an Installed Add-ons link (at the bottom right). If you follow that you will find the ExtendUnits6 package. That will take you to the documentation. _______________________________________________________________ That should work. If you have problems please contact me. djmpark@comcast.net