This forum is for ODS and Base Reporting questions -- CREATING reports with PROC PRINT, PROC REPORT and/or PROC TABULATE. Since you would not use ODS or any of those procedures to READ an external file into a SAS dataset, then this is probably not the place to post your question.
Your question is probably best answered by Tech Support, but in order for them (or anybody) to answer your question, they will probably need to know which software application created the .RPT file??? COBOL? Easy-treve? Paradox? Fox-Pro? Visual Basic?
SAS can read many different proprietary file formats (such as Oracle tables, Excel files, XML files, etc.). SAS can also read files via ODBC or OLE-DB or JDBC. Tech Support really is the best place to get your question answered. To post a question to Tech Support, go to: http://support.sas.com and in the left-hand navigation pane, click on the link entitled "Submit a Problem".