Impact Licensing – Service Update
Throughout today (Dec 2nd), our licensing service provider, Nalpeiron, experienced several outages caused by issues at their hosting provider, Azure. Nalpeiron has confirmed that full service has now been restored, they do not expect further disruption, and they are implementing additional safeguards to mitigate similar issues in the future.

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Troubleshooting

HTTP Response Code 417: Expectation failed

Modified on: Wed, 8 Feb, 2023 at 8:25 PM

PROBLEM: HTTP Response Code 417: Expectation failed.
Example: HTTP Response Code 417: Expectation failed.

SOLUTION:
Some proxy servers interfere with the HTTP packets sent between client and servers on a network. The .Net HTTP layer adds an 'Expect: 100-Continue' header that some servers choke on and return a 417 error. The solution is to configure the \Windows\Microsoft.NET\Framework\v2.0.50727\CONFIG\machine.config file and merge the following configuration into the XML.

<system.net>
    <settings>
    <servicePointManager expect100Continue="false"/>
   </settings>
</system.net>

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