simple Question. How to set a fixed Discount (for instance -15%) for a fixed User ?
For some known Clients our shop should set a discount, when the user is logging in.
You can't restrict a discount to a user group. However, you can restrict a discount to a user group in the Business edition.
In Joomla 1.7 you can easily create new user groups and attribute several groups to a user (for joomla 1.5 you would have to use DJF ACL).
You could create a specific group for that user, add that group to that user and then set that group for that discount and that would do what you want.
