As we know generally system will not allow user to delete and change some master data from the system, when it is already use somewhere.
Like - Order is already booked for some material & same material class characteristics changes required. System will not allow the same. System will restrict the user to delete characteristics from the class. because it is already use in some configuration as well as in other master data (Ex - Dependency)
In this kind of case SAP has given one report. Name called - RMCLMDEL.
Note: Authorization of executing this report should be limited.
This report will delete the characteristics with the assignment.
Step 1: Go to SE38 transaction code.
Step 2: Enter report name (RMCLMDEL) and click on display button.
Step 3: On report we have button called Direct processing. Or click on F8 Button to process.
Step 4: The new page will open with the name "Delete Characteristics from class with assignment"
Step 5: Fill class, class type and Characteristics name, which user want to delete.
Step 6: Just click on execute button to delete the characteristics from the required class.
(While process, system will give warning message just ignore it and process)
When characteristics already used in sales orders with the assign values That time user has to remove that characteristics value from the order.
In some case its not easy to remove value. (In the case - mandatory characteristics of the order, or other case like dependent characteristics value)