C# vs C++ SMPT SERVER

We have a SMTP server written in C# for Windows server. We would like to discuss development with a programmer - would the server perform better in c++? The smtp server is multithreaded - spawns up to 1000 threads, doing DNS lookup and socket connections. Is there any issues with using c# over c++. We are happy with the SMTP server but looking at ways to improve performance - maybe port to Linux. All feedback is appreciated - on answering questions we will make a decision to develop further - either port to c++ and linux. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform Simply reply to questions so we can move forward