The same here with the last version, free edition.

I have updated to 3.6.6 but now have this issue when I didn’t before 🙁

Testing …

[SU] Checking array(3) { [0]=> object(WP_Http_Cookie)#11303 (5) { [“name”]=> string(11) “SU_REMEMBER” [“value”]=>
string(68) “1%7C34446718%7C1470128213%7C6af8bf994c6f57bda19df44256a83917567ca73b” [“expires”]=> NULL [“path”]=>
string(1) “/” [“domain”]=> NULL } [1]=> object(WP_Http_Cookie)#11304 (5) { [“name”]=> string(9) “seulepage” [“value”]=>
string(3) “oui” [“expires”]=> NULL [“path”]=> string(1) “/” [“domain”]=> NULL } [2]=> object(WP_Http_Cookie)#11305 (5) {
[“name”]=> string(14) “su_accesstoken” [“value”]=> string(32) “62391799e7ea8279f178a47283a2672f” [“expires”]=> NULL
[“path”]=> string(1) “/” [“domain”]=> NULL } } [SU] Saved login – IN… [SU] Posting
…https://weddings.popupsites.com/blog Array ( [0] => Array ( [message] => This webpage is not available. Please try
another page. [code] => -1000000 [struct] => discovery\Discovery [type] => reason [meta] => Array ( )

)

[NXS_FIELDS] => Array ( [_token] => c5238334603f426d019095f6d12eb1d3 [_action] => submitUrl

BBCode you used is not allowed.

=>
https://weddings.popupsites.com/blog [review] => Test Post from Popup Weddings
Blog\nhttps://weddings.popupsites.com/blog [tags] => Weddings [nsfw] => false [user-tags] => [_output] => Json
[_method] => create [language] => EN )

[NXS_RESP] => Array ( [_timestamp] => 1470333770 [_sub_errors] => Array ( )

[_success] => [_error] => [_reason] => Array ( [0] => Array ( [message] => This webpage is not available.
Please try another page. [code] => -1000000 [struct] => discovery\Discovery [type] => reason [meta] => Array
( )

)

[NXS_FIELDS] => Array ( [_token] => c5238334603f426d019095f6d12eb1d3 [_action] => submitUrl

BBCode you used is not allowed.

=>
https://weddings.popupsites.com/blog [review] => Test Post from Popup Weddings
Blog\nhttps://weddings.popupsites.com/blog [tags] => Weddings [nsfw] => false [user-tags] =>
[_output] => Json [_method] => create [language] => EN )

)

[loggedIn] => 1 [su_version] => [thumbCDN] => nb9.stumbleupon.netdna-cdn.com [newDiscovery] => 1 [discovery]
=> Array (

BBCode you used is not allowed.

=> [tags] => Array ( )

[topic] => 0 [language] => [firstrater] => [review] => [nsfw] => [rating] => -1 [_success] =>
[_fatal] => [_error] => Array ( [message] => Failed to add URL [code] => 1 [struct] =>
discovery\Discovery [type] => error [meta] => Array ( )

)

[_reason] => Array ( [0] => Array ( [message] => This webpage is not available. Please try another
page. [code] => -1000000 [struct] => discovery\Discovery [type] => reason [meta] => Array ( )

)

)

[_captcha] => [_version] => 2.0 [_name] => Discovery [_group] => discovery )

)

) Array ( [0] => Array ( [message] => This webpage is not available. Please try another page. [code] => -1000000
[struct] => discovery\Discovery [type] => reason [meta] => Array ( ) ) [NXS_FIELDS] => Array ( [_token] =>
c5238334603f426d019095f6d12eb1d3 [_action] => submitUrl

BBCode you used is not allowed.

=> https://weddings.popupsites.com/blog [review] => Test
Post from Popup Weddings Blog\nhttps://weddings.popupsites.com/blog [tags] => Weddings [nsfw] => false [user-tags] =>
[_output] => Json [_method] => create [language] => EN ) [NXS_RESP] => Array ( [_timestamp] => 1470333770 [_sub_errors]
=> Array ( ) [_success] => [_error] => [_reason] => Array ( [0] => Array ( [message] => This webpage is not available.
Please try another page. [code] => -1000000 [struct] => discovery\Discovery [type] => reason [meta] => Array ( ) )
[NXS_FIELDS] => Array ( [_token] => c5238334603f426d019095f6d12eb1d3 [_action] => submitUrl

BBCode you used is not allowed.

=>
https://weddings.popupsites.com/blog [review] => Test Post from Popup Weddings Blog\nhttps://weddings.popupsites.com/blog
[tags] => Weddings [nsfw] => false [user-tags] => [_output] => Json [_method] => create [language] => EN ) ) [loggedIn]
=> 1 [su_version] => [thumbCDN] => nb9.stumbleupon.netdna-cdn.com [newDiscovery] => 1 [discovery] => Array (

BBCode you used is not allowed.

=>
[tags] => Array ( ) [topic] => 0 [language] => [firstrater] => [review] => [nsfw] => [rating] => -1 [_success] =>
[_fatal] => [_error] => Array ( [message] => Failed to add URL [code] => 1 [struct] => discovery\Discovery [type] =>
error [meta] => Array ( ) ) [_reason] => Array ( [0] => Array ( [message] => This webpage is not available. Please try
another page. [code] => -1000000 [struct] => discovery\Discovery [type] => reason [meta] => Array ( ) ) ) [_captcha] =>
[_version] => 2.0 [_name] => Discovery [_group] => discovery ) ) )

Just to add my site is HTTPS so not sure if this may be the issue. Shall I log a support ticket?