Rodd-

>

>lhFile = fopen(lcFileName,10)
>if lhFile = -1
>   Loop
>else
>   ... do the conversion
>endif
>

>
>However, for some reason this doesn't seem to be catching the fact the the file is still being created.

This is probably obvious, but just in case it isn't, to add to Sergey's reply, 10 opens the files for read-only access which will allow sharing. Either 11 (write-only) or 12 (read-write) will open the file exclusively, so if another process has it in use, the function will fail.