I'm using DTS and Paradox (version 9) and Microsoft driver to work with Paradox has some problems, for example you cannot work with password encrypted tables. I'm trying to use now the ODBC driver delivered with Paradox (created by Intersolv) and it seems to work quite fine, although I've the problem that it's asking me the password when I want to pass it by code. May be you should try it.

Another thing it to check if the tables are corrupted.

Josep.