On Tue, 6 Aug 2013, Volker Schmid wrote:

> 2013-08-06 10:09:31 : CURL: Establish HTTP proxy tunnel to xxxx.xxxx.de:443
> 2013-08-06 10:09:31 : CURL: Proxy auth using Basic with user 'testuser'

This says that libcurl already selected to use Basic for this request. When it
already has selected the Basic method and included such a Proxy-Authorization:
header, then a 407 response will mean failure.

Since you say you selected multiple methods and yet libcurl came to the
conclusion it should use Basic directly, it would indicate that it switched
off the ability to use the others because it was built without support for
them. I think you should verify that the libcurl that's used actually supports
NTLM and digest.

Are you sure that's the complete log?

-- 
  / daniel.haxx.se
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