add functionality to compiled OCX

Question

We have an old OCX, that used in old VB application. Both of them do not support by developer now. and source code also not available. OCX contains a function which calculate a value and now we have to change the formula of calculation. Is there any way to override method and create a news ocx with same functionality?

Edit: ocx contain a date picker which using mscomctl2.ocx, our formula is based on selected date, so if we can find a solution to change date after selection, we can reach to our need.

Answer 1

There is another way, Safe to use only if you are owner of that ocx file. You can use vb decompiler to get source code from your ocx file so you can modify and create new source code. Here is a decompiler

http://www.vb-decompiler.org/