Failed Import, ISAM 172 Error, Corrupt Indexes

Working with INFORMIX 7.32, our normal import to the database failed today. Upon further investigation, I found this error (below). The oncheck -pt indicated that the table could not be accessed. I ran anoncheck to check the indexes, and it seems several of the database indexes are either fragmented or produce an ISAM 172: Unexpected error. We had recently added a chunk (chunk 14, i BELIEVE) to the database, because it had gotten full. Any suggestions, reccomendations, or other help? Is this a failing hard drive? --- 11:08:38 I/O read chunk 9, pagenum 4, pagecnt 1 11:08:38 I/O read chunk 9, pagenum 4, pagecnt 1 11:08:38 Assert Failed: WARNING! I/O read chunk 9, pagenum 4, pagecnt1 11:08:38 Who: Session(569, xux@afge, 6313, -687635928) Thread(728, sqlexec, d7023518, 1) 11:08:38 Results: Cannot use TBLSpace page for TBLSpace 9437185 11:08:38 Action: Run 'oncheck -pt 9437185' 11:08:38 See Also: /usr1/informix7.23/af.2d8c9f6