>>>>
>>>>This error may indicate that you have SET EXCLUSIVE ON and Select tries to use some table, not open yet in the code. I would fix this problem, i.e. eliminate the error. TRY/CATCH is supposed to be used when error is more elusive, e.g. some network drive may exist or not, some import file is supposed to have specific format, etc.
>>>
>>>I don't think I have SET EXCLUSIVE ON in any part of my application. My suspicion is that the network or server sometimes has a delay in allowing files to be opened.
>>
>>Maybe, it is a good idea to open all needed tables without relying on implicit opening by SQL-Select?
>
>Actually, this is what I used to do. But now I am converting the application to a 3-tier design with the purpose of using either VFP data or SQL Server. So now I am passing to the DA tier an expression that may need any number of tables to be opened. So unless the function in DA tier parses the expression and finds all tables that need to be opened, it is difficult to open the tables beforehand. I believe that by wrapping the macro in TRY/CATCH will eliminate run-time errors. Also, I think I need to include SET REPROCESS TO a large number of seconds.

There are connection properties you can set to control retries, similar to SET REPROCESS for FoxPro tables. That will handle slight delays of the type you describe.