In the IDE click Help Menu > Register and authenticate using your email and JetBrains password. Import the certificate you exported from the Ke圜hain We have an Internal Root Certificate that needs to be installed. The proxy advice from JetBrains was a bit confusing, because for us the solution wasn't proxy and nothing was blocking or substituting anything. You can see the 'last seen' date in the website shows usage and the people affected. However for some people in the organisation it worked and some others (sitting next to each other with the same OS) it failed and they got this error. If it's not a corporate network and you can't control these connections, the end users who faced the issue can use offline activation codes, from their profiles. Please contact your organization IT helpdesk or ISP support to get it resolved. Note that this proxy server may be completely transparent to you and may work without any explicit proxy configuration in your system.

Proxy server between you and our server ( ) that intercepts SSL traffic and substitutes our certificate with its own one, which is different and will not be accepted by the IDE. It doesn't work because something between our site with its correct certificates replaces these certificates. OK, I've contacted support and they say it's a proxy issue &/or something replaces the certificate:

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