Membership provider ( how to start ? )

Hi 

I'm  quite new ASP programmer


I need implement security in my project, and I need use mempership to do so.

The thing is I have already database, and I don't want to add some extra tables into DB. 

I have just simple: User Table ( ID, Name, Password ) and that's it. 

If there any chance to use this table with membership ? 
 
I found some tutorials how to use or configure membership, but none of them show how to do such thing that I need. 
 
Thanks in advance. 


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