I think to remember that there was an issue with extension downloads not honoring the proxy settings, but could not find it in the release notes. Please make sure to be on the latest ClearPass hotfix level for 6.11 or 6.12.
Further, some extensions are now posted to the support portal, so that may be a workaround for you as well. If nothing works, please report to TAC as they should be aware of such issues, if there are any.
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Herman Robers
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If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
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