XLS file and dll version

I would like to find out how excel file will bind itself with particular version of excel dll

We developed excel VBA application using excel 2003 SP3 and the try to open under excel 2002 SP2 environment. It started giving compilation errors.

in Excel 2003 version we have so many new dlls.I found out that the problem
is happening because only one dll called REFEDIT.DLL which is version 1 in excel 2002 SP2 and version 12 in Excel 2003 SP3.

I copied the REFEDIT.DLL version 1 from excel 2002 SP2 to Excel 2003 SP3
environment and saved the excel file again in 2003 SP3 environment and opened that file in excel 2002 SP2 environment and it started working.

My question is why only one dll REFEDIT.DLL was causing issue with backward compatibility to excel 2002 SP2 and not other dlls. Excel 2003 SP3
have so many latest dlls compared to 2002 SP2.

My another question is how xls file you save from excel keeps references to a particular version of the dll which happened in above scenario.

Hello excelsandpstarter,

The RefEdit control is not part of the standard VBA tool box of controls. It is an additional control than can be added to the tool box. This means it is up to you to import the correct version of the control. Each time a new version of Excel becomes available, many changes take place not only in Excel but also in the Windows system code. This directly effects how the DLL operates. Whether it will be backward compatible depends on many factors.

Sincerely,
Leith Ross