Known applications which don't support NTLM Authentication

Article #: Product Castle
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Some applications do not support NTLM authentication.


The following is a list of applications which are known not to support authenticated proxies (NTLM Identification / NTLM Authentication / Proxy Authentication):


If the application listed above doesn't have its own article, use the steps below:

  1. Create a custom category for the appropriate domains — see
  2. Avoid using the Guardian category that the domain in question belongs to, as this may contains domains for other applications.

  3. Add the following to authentication exceptions:
    • The new custom category created in step 1
    • SSL /CRL category
    • Software Updates category


  4. Create an Allow web filter policy for custom category created in step 1 — see
  5. Move the new policy to be above any block policies in the Web filter policies table — see
  6. If you continue to experience issues, filter the Web filter logs by the IP of a test client, attempt to open the site / application, and add the domains that appear in the web filter logs to the authentication exceptions.


Last updated: Author: Contributions by:
27th March 2017   TE