EXCEL file cannot be accessed for Recalculation of worksheet via VB.

I have a Vb6 project I run. One of the forms called “APPROACHES” is connected to an Excel file called “APPROACHES”. Anytime I visit the APPROACHES form and give a command to open and calculate worksheet in the “APPROACHES” file, I receive the following Error message:

Run-time error ‘1004’
‘APPROACHES.xls’ cannot be accessed. The file may be corrupted, located on a server that is not responding, or read-only.

If I leave the “APPROACH” form to another and issue the same command from there I encounter no such problems. Any help from kind fellows?