Unfortunately  I have not done a lot with .NET the last months, but more with management of quite a large system that is existing for more than six years now (based upon VB6, ASP and Oracle).

At the moment we are thinking about rebuilding the complete system. Redesign the architecture, use the latest tools (e.g. .NET, Biztalk) etc. because the current environment has all kind of constraints. The biggest problem is that the system is very big, not well documented, doesn't have a solid architecture anymore and development of new functionalities takes very long.

Question: Does a new system solve all the issues?

I think a new solid system will not solve all the issues and that change and release management should also have the same attention as the new sytem. I think that if you create a new system without having good procedures for change- and release management you will end up with a similar system within a couple of years.