Greetings.
In a LAN, while a user is working on an XLS file, form many other hosts a
tool I have to write should be able to view information from it (using ODBC).

My test works only when the XLS file is closed.
When it is opened (on the machine where they modify it through Excel), I get:
The Microsoft Jet database engine cannot open the file '(unknown)'.
It is already opened exclusively by another user...
(Another strange case: it happened that my code receives 'actual' values
when the xls is closed, 'possibly older values', without returning the above
mentioned error, when it is opened).

Operations on that book.xls is mandatory (ie: I cannot translate it into
another db format).