RFC FM call from VB.

Hi,

we are calling some RFC funcitons from VB. Machines with Sap GUI 46D we don't get any error and process is completed successfully

but machines with 620 GUI,one of the FM is not executed even though the data set is same for both operations, using same file for upload.

Please help me to understand the possible reasons for this failure with 620 Gui.

thanks

Thanks.