>We have customers how use our application via a Citrix connection. Sometimes when they start the application they get the error:
>
>"Error reading file r:\vtc\data\vl_bill.dcx"
>
>The error occured again yestedsay, but the DCX file is dated 5/25.
>
>Is this file necessary, or can I remove it?

For a regular table you have

DBF - table file
FPT - memo file
CDX - compound index file

For a database container you have

DBC - table file
DCT - memo file
DCX - compound index file

so, don't delete the DCX.

If the file is corrupted then you would get the error every time. It sounds like it's intermittent, maybe there's a problem with a network connection or a server disk subsystem.