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WebDAV

WebDAV stands for Web Distributed Authoring and Versioning.

WebDAV is an extension of HTTP which allows clients to create, change and move documents on a server.

Checking if a webserver supports WebDAV

A webserver that supports WebDAV returns a DAV header when the Options method is requested.

Thus, in PowerShell, the existence of such a header can be checked with:

(invoke-webRequest http://live.sysinternals.com -method Options).Headers.DAV