SAP Message 63255 - Characteristics & in class & are mutually exclusive & &

Diagnosis
You have selected at least two fixtures and fittings characteristicsthat exclude each other.
These characteristics are &v1&.
In Customizing for the representative lists of rents, groups aredefined in the characteristic class "&v2& &v3&".
A maximum of one characteristic can be assigned for each group. Youhave assigned more than one characteristic from the group &v4&.

System Response
Characteristic assignment is not correct.

Procedure
If this message appears during a test run (after choosing 'Save'),cancel the test run by pressing F12 (Cancel).
Delete either the assignment indicator or the number of points for oneof the characteristics &v1&.
In the characteristics class detail screen, you can use the function"Display all" to display the groups defined in Customizing.