How to set relative path in web.config in ASP.NET web application for accessing files?

Hi,
I need to access and open a file in web application. I deployed my web application in C:\inetpub\wwwroot\MyWebApplicatiion\. My files are at C:\inetpub\wwwroot\MyFiles\

In my web.config file, I am having setting for my file path:
<setting name="File_Path" serializeAs="String"> <value>/MyFiles</value> </setting>
In my code, I am trying to map the path as: Server.MapPath("~/" +Properties.Settings.Default.File_Path).
It is returning the path as "C:\inetpub\wwwroot\MyWebApplicatiion\MyFiles", but I am expecting C:\inetpub\wwwroot\MyFiles\
To get the expected path, how to set the relative path in web.config file

Thanks in advance...
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