Help with DBase Table Coruption

I have Built an App for Laptop Salesman that I Send a Ziped Data File to
them every night my program uses Dyna Zip to unzip the file and then I use
AddIndex(IdxName,IdxName,[]) to create the required indexes. The Process
seems to work fine no errors my program can do standard calls to the tables
no problems, but my program uses CodeBase to do word lookup on description
fields and it Fails. I have talked to codebase(Sequiter) and sent them my
files and they tell me that part of the DBase file header is Corrupt. This
leads me to believe that the BDE 5.00, 5.01 is some how corupting the
table(s) when the indexs are created.
  An other thing that makes me belive it is the BDE is in fault or a windows
DLL is some how causing the problem is that the program workes perfectly on
10 machine and has failed on 2 machines also the same algorithm as worked on
25 machines for 2 Years with out a single problem. The first machine I got
it to work by formating the hard drive and reloading windows 98 then
installing my program and then it worked fine the current problem  is that I
can not format and restart due to user data.
  So far this has only happened on windows 98 machines

Thanks
Steve Bossen
J&B Importers, Inc.