Infection MDAC ActiveX Code Execution (type 350)

Problems like this are really more of a vulnerability issue and not truly malware. How people write their website code, how old / un-updated the software they write it with, and how secure the servers that host it are really the areas to look at. Issues here are commonly referred to as code injection ( see: http://en.wikipedia.org/wiki/Code_injection ) The things we do in this forum are not going to find problems in your code. None of these malware scanners will since they are not design for this purpose.

You are going to need to have a very good webpage developer check the code for security issues and you need to verify that all software being used has been updated to include all security patches. In addition, you need to make sure that the server hosting the website also has been fully updated.