You can specify the permanent defaults for controller types and controller settings to match the way you prefer to work.
The following defaults are written to the 3dsmax.ini file:
You specify default controllers by choosing Controller Assign from on the Track View menu (see Assigning Controllers). When you choose a controller in the Assign Controller dialog you have the option to click Make Default before clicking OK.
Clicking Make Default assigns the chosen controller as the default for all parameters using that data type. It has the following effects:
You can specify the default settings for many controller types, or reset controllers to their factory settings on the Preferences dialog.
To specify default controller settings:
The default Position controller is Position XYZ.
The default Rotation controller is Euler XYZ. Euler XYZ Rotation behaves quite differently TCB rotation. It gives you three function curves to manipulate, but does not allow rotations of greater than 180 degrees between keys. Use the TCB controller for continuous rotation and rotation greater than 180 degrees.
The default Scale controller is Bezier.
Once you click OK, the controller defaults are changed. Changes to the controller default settings are written to your 3dsmax.ini file and become the defaults for all newly assigned controllers and all new scenes.
You can also revert to the original program defaults for all controllers by clicking Preference Settings dialog Animation panel Controller Defaults group Restore To Factory Settings.