UNCAuthenticationPassThrough Support Limitation in IIS 5.0

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Article ID: 286401 - View products that this article applies to.
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When you consult a page that is physically located on a remote virtual directory, the UNCAuthenticationPassthrough metabase property allows Internet Information Server 5.0 to access remote files using client (browser) credentials. However, this option is not currently supported, although this feature is documented in the IIS Resource Guide.


This feature has not been extensively tested by the IIS team with the current version of this product. This scenario also increases the number of server message block (SMB) sessions between the redirector on IIS servers and the remote SMB server, and requires more resources on the SMB servers.

Even if you do not use the UNCAuthenticationPassthrough feature, Microsoft recommends that you replicate contents locally to the IIS server rather than access file resources on network servers. This approach enables your Web sites to scale up and down, and to avoid access to the centralized file server (which may become a performance bottleneck).


Article ID: 286401 - Last Review: October 23, 2013 - Revision: 3.1
  • Microsoft Internet Information Services 5.0
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