Unknown error (invalid-json). Please contact an administrator for more info.

I also met the same problem with 2.0.2:
Unknown error (invalid-json). Please contact an administrator for more info.
After I update my php from 5.3.3 to 5.6.16 on my iis7.5 2008 R2 server.

If I back to php 5.3.3 it will ok but it will get problem when I use php 5.6.16.

So i also open the file curlpost.php and changed the line 79# from CURLOPT_SSL_VERIFYPEER => ture
to
CURLOPT_SSL_VERIFYPEER => false,
and then it can run very well on php5.6.16.

But I guess it is a potential problem there.

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