SAP Note 19078 - Error in index series 000

Symptom:

Index key 000 is rejected.

Cause and prerequisites

Conversion from R/2 to R/3 has been made.
In R/2, the index series 000 was also accepted as initial value for the indexing. In R/3, the value is blank.

Solution
Either globally change all indexes from 000 to blank or change the data transfer program R/2 -> R/3.