I have a bar coding program which refers to an Excel workbook as an ODBC database. I'm using Excel's =now() function within the worksheet to derive date codes. The problem I've run into is that the formulas in the worksheet are not updated when the bar coding program accesses the worksheet. I'm thinking that's because the file isn't actualy opened when accessed by the external program.

1) Am I correct in thinking the external program is not actually opening the file, but simply reading what was stored in it last?
2) Is there a way to have an external program open, then save, then close a file when accessing it?
3) Perhaps even better, is there a way to have my Excel sheet update itself periodically (at least once a month, within the first few hours of the first day of the month)?
4) Are there other solutions I've not thought of?

I'm working on having the external program derive the date code on its own. However, that's easier said than done, as it uses a lookup table (another reason I'm using an Excel sheet as my database) to find the code relative to the actual month and year. I'd rather have Excel do all the work, and then have the external program harvest the data from the Excel sheet.

Thanks in advance,

-Dan