Quite surprisingly I did not see many people coming across this issue using crystal reports, I do not find this issue addressed anywhere else even on SAP crystal community discussion network , So I decide to post it on a blog. It may help some since I experience this on CR 2013 sp1 for the first time.
Application: Crystal Reports 2013 SP1
Issue resolve : re-map connection(ODBC> OLE-DB>Oracle )
There are 2 solutions:
#1. Re-map your database connection, If IT department recently upgraded Oracle database from 10g to 11g there are higher chances that your crystal reports may not read character set due to an existing connection. So make sure you re-map connection using OLE-DB(ADO) Microsoft OLE DB provider for Oracle. (my issue was resolved fixing connection but most threads on web search were about #2)
#2. Say if you are bringing data set from two different sources (separate database) then this error can generate because your field have international or blank text in primary key tables. In that case you use length count on the field on your both queries from database. Result should be same on both queries for example one query says 7 and the other query says 12. This is the problem both query should have even amount of length for crystal reports to read data. else it will collecting values+ junk+ space that generates ORA-29275 Partial Multibyte error, Connector issue.
Check the length on each query which you put up the join on.
Select [FIELD1], LENGTH(FIELD1)
I think if you follow #1, That should take care of #2 automatically.