This is related to the question you posted in the DW forum, albeit it is not about DW specifically so I am posting my thought here.
IMHO, you should only ever use a wizard or have an application generate code for you when it is absolutely necessary and, moreover, you should never let an application generate code for you when your entire site functionality revolves around it; in your case your entire authentication process.
My biggest gripe against this is that editors don't tend to generate "clean" code and it is often bloated with unnecessary calls and then, when you have to go in and make a change manually, you have to figure out what type of logic the editor used to create the code whereas if it was your code, you would know exactly what was going on.
While this might save you time in the short-term, over the long-term it is bound to create more clock hours for you then necessary. (This will also lead to an increased consumption in caffinne, nicotine, TUMS, and asprin)
Lastly, again totally my opinion and I mean no disrespect by this as it goes for any would be programmer, but one should learn how to program in their discpline (read as fully understand the language) before they ever let an editor generate any form of code for them. The reason for this is obvious, you won't ever learn anything if you have an editor do the work for you.
Just my 2 cents, and I understand that you are learning so don't take this as an attack or a flame of any sort, I just think that you should research your problem on authentication before you go to see if Dreamweaver can implement the solution for you.
Read this if you want to know how to get a correct reply for your question:
^^Took that from planoie's profile^^
^^Modified text taken from gbianchi profile^^
Technical Editor for: Professional Search Engine Optimization with ASP.NET
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