Generally, concatenating strings is a bad thing in .Net and a huge waste of resources. You're probably better off with StringBuilder.

>May be it's paranoia, but assuming the original ReturnMessage is quite long, this would be waste of resources. I am thinking may be I better off using a builder and just concatenate strings here instead?
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>I haven't run any performance tests yet, in fact, I'm deep in re-factoring today - I created a bunch of new classes and changing code to get rid of passing messages by reference around but rather re-use the new classes.
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