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cURL error 51

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If you get an error while trying to to connect/activate Platform 5 that looks like this:

Screen Shot 2017-01-17 at 19.20.53.png

The Problem

The server you’re hosted on uses a very old version of CURL and / or OpenSSL, the library used to connect to other servers.
Since version 0.9.8j openSSL has supported SNI ( Server Name Identification ), curl uses this to make sure the server its connecting to matches the certificate. Even IE6 supports this checking.
Because your version of openSSL is so old curl cannot use SNI and this error is produced.

The Solution

Please ask your hosting provider to update both your SSL library and CURL and you should be ok.
The OpenSSL version used should also be 1.0 or higher, or an equivalent other SSL library that supports SNI.

We don’t like telling people to contact their hosts. Unfortunately, there are two solutions for us here: fix it for everyone by using an insecure connection, thereby creating security issues, or asking you to contact your host. We’ve chosen the latter. Feel free to send your host this page and specifically the technical paragraph below.

What to do if your host doesn’t want to fix it?

As the software we’re asking your host to use is over 8 years old and several major security problems have been found in these libraries through these years, you should run, not walk, away from your host if they refuse to do this.

Technical background

  1. A version of CURL that supports it, at least 7.18.1, according to the change logs. CURL 7.18.1 was released on March 30th, 2008.
  2. This version of CURL should be compiled against a library that supports SNI, usually OpenSSL 0.9.8j or higher as that enables TLS by default, see below. 0.9.8j was released on January 7th, 2009.
  3. To use TLS 1.0 or higher and not use SSL v3. Because SSL v3 is insecure, you shouldn’t use that anyway.

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I have connection issue Platform 5 Please help me?



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