When you create or administer a Web site or virtual directory, the option to browse for the physical location where the content is stored for that site or virtual directory includes mapped drives. This may be interpreted as a way to keep the content on a network share accessible through the mapped drive; however, because the nature of drive mappings, this is not a viable option. If you prefer to keep your content on a remote computer, then create the Web site or virtual directory with a universal naming convention (UNC) path to point to the share on the remote computer.
A possible work around is to log in to the console of the Web server as a user who may need to be authenticated through the Web server, and then create the mapped drive as a persistent drive (Reconnect at Logon) for that user account. This can cause performance degradation because the user account that you are connecting with may need to be authenticated twice for access, once by IIS and a second time to create the mapped drive.
The preferred method of accessing content for the Web server that exists on a remote computer is to use shares that follow the universal naming convention (UNC).
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