Invalid data or no response: The receiving plugin may not be activated at:

I’m trying to set up the MHMCS Provisioning on a multisite installation and keep getting an error message that has been mentioned on these forums before:

Invalid data or no response: The receiving plugin may not be activated at: http://domain.com

My setup is:

Linode

LEMP

PHP-FPM

WHMCS directory: domain.com/clients

Template: tried both portal and default (though if it needs to be portal that should be mentioned in the usage instructions)

Server: double-checked hostname (domain.com) and IP address. The “Login to WordPress” button works as it should

Any help would be appreciated as my main reason for getting a WPMU Dev membership was for the WHMCS plugins. Thanks.

  • Mason
    • DEV MAN’s Sidekick

    Hmm, I wonder if running Nginx over Apache has anything to do with. I don’t believe it should since you’ve verified everything else in your WordPress install is working.

    Let me get the developer to provide some feedback here. Thanks!

  • Arnold
    • El Macho WP

    To see what you are actually getting back from the plugin on the WHMCS side go to Utilities | Logs | Module Logs and enable logging. Run your transaction and look at the log to see what’s being returned.

    A common problem we’ve found if the WHMCS and WordPress sites are run on the same host is that some hosts in the name of security firewall local loopback. That means that one site on the host server can’t talk to another site on the same host server. Your WordPress login would work because that is coming from your Browser and hence is outside.

    If this is the case the only fix is to get your host to allow the connection.

  • Sam
    • WPMU DEV Initiate

    This is what I get as a response:

    Array

    (

    [0] =>

    [1] => Array

    (

    [url] => http://domain.com

    [content_type] => text/html

    [http_code] => 500

    [header_size] => 909

    [request_size] => 827

    [filetime] => -1

    [ssl_verify_result] => 0

    [redirect_count] => 0

    [total_time] => 20.145495

    [namelookup_time] => 0.134483

    [connect_time] => 0.134641

    [pretransfer_time] => 0.134647

    [size_upload] => 578

    [size_download] => 0

    [speed_download] => 0

    [speed_upload] => 28

    [download_content_length] => -1

    [upload_content_length] => 578

    [starttransfer_time] => 20.145406

    [redirect_time] => 0

    [certinfo] => Array

    (

    )

    [redirect_url] =>

    )

    [2] =>

    )

  • Sam
    • WPMU DEV Initiate

    So are you saying that the only solution is to get my host to allow the connection? If so, any pointers on how I could do that? I’m new to system administration and didn’t realize this was going to be an issue.

  • Arnold
    • El Macho WP

    That means the plugin on the wordpress side is installed and working. So If you can communicate from your browser but not from your server then it’s probably a blocked loop back. The test you ran earlier with the Module log should have showed something similar but it isn’t gtting through.

    You should discuss it with your hosting company.

  • Sam
    • WPMU DEV Initiate

    Well, since I’m on Linode, I kind of am my hosting company. And since it seems like this is a known issue (though not mentioned in the plugin docs), do you think you could give a little guidance on how I (or anyone else that runs into this problem) could fix the server so that it didn’t block the loop back? I’m still not exactly clear about what is going on.

  • Sam
    • WPMU DEV Initiate

    After some further investigation, I am pretty sure that there are no firewalls on my network at all. I have a clean installation of Ubuntu and as far as I can tell, that does not come with any firewalls. So, if I understand correctly, there is no firewall blocking the local loopback. What are some other things that could be causing the invalid data error?

  • Arnold
    • El Macho WP

    You would need to turn on logging and run the transaction. You were getting a 500 error form the server when you tried so you need to see what the server thinks is happening.

    Checking the obvious. If you use SSL you need to use it on both sides. When you setup the server on WHMCS the Domain is just the domain name. No http:// in front of it. I’m assuming it’s correct because you said the login from WHMCS button worked.

  • Arnold
    • El Macho WP

    Details vary endlessly. There is probably an error log wherever your Apache httpd.conf file says it is.

    You’ll want to turn up the logging level

    https://httpd.apache.org/docs/2.2/logs.html

    You’ll probably need to turn on mod dumpio so you’ll get full logging.

    https://httpd.apache.org/docs/2.2/mod/mod_dumpio.html

    All this assumes your even running Apache.

    Then you’ll need to know how to interpret the error messages. But frankly if your asking this kind of low level questions you’ve got a lot of studying to do to run your server. Can’t you get your hosting company to assist?

  • Sam
    • WPMU DEV Initiate

    Unfortunately, I can’t get my hosting company to assist as I’m on Linode. Also, I’m on a LEMP stack, not a LAMP stack. I am well aware that my sys admin knowledge is very limited. I’m simply trying to get this set up as quickly and as cheaply as possible so that I can test my startup’s MVP, however, I’d like to be on infrastructure that I can eventually scale if/when I have the ability to hire a sys admin.

    It seems like you can’t offer the help that I need without getting access to my server. Is that correct?

  • Mason
    • DEV MAN’s Sidekick

    Hiya Sam,

    Stepping back in here for a minute assuming Arnold has already gone for the day.

    Quite honestly, this is beyond our ability to support both in terms of our staff and what can be done through the forums.

    My thought would be that if you’re looking to get this going on the cheap, use a hosting provider that does more of these server-level tasks for you. Any of them will “upgrade” your server package for you down the road and grow with you as your business has the need and budget to handle them.

    Every hosting provider has folks with good and bad experiences. In my own experiences BlueHost and GatorHost both do a great job of getting the server stuff supported so you can focus on WordPress.

    It’s tricky to find the right balance when starting out, but when you start to factor the “time” costs to you – or what would happen if the site suddenly got a lot of attention and goes down? That’s not a time where you wanna be “the guy” who has to fix it.

    Just some friendly (though unsolicited) advice :slight_smile:

    We do wish you all the best on your project as you get started. If you run into any other specific issues with this plugin please open a new ticket and we’ll gladly assist.

    Thanks.

  • Sam
    • WPMU DEV Initiate

    I appreciate your “unsolicited” advice, but I’ve had sites on HostGator (I assume you meant HostGator when you said “GatorHost”:wink: for years and they are awful in terms of performance. I’m not looking to be on shared hosting and Linode’s VPS is widely acclaimed as the best performance for your buck. I really don’t want to be wedded to an underperforming host, nor do I want to have to take the site down for however long it would take to transfer it from one host to another.

    I understand that you can’t provide assistance in every circumstance, especially when it has more to do with the server than anything WordPress-related. However, this does seem to be a recurring issue (as evidenced by the fact that there are multiple posts on this forum with that error message), it does not seem to be related to firewalls (as was suggested in a previous response), and even if it was a the firewall issue, that issue is not mentioned in the “known issues” section. A mention there might at least help the many other people who have run into this problem.

  • WP Chef
    • Site Builder, Child of Zeus

    I’m having the same problem here… but only on one domain

    I have another domain with the same web host that does work….

    There has to be some kind of inconsistency between the two installations but I can’t pin point…

  • WP Chef
    • Site Builder, Child of Zeus

    Ah ha, took Arnold’s advice and enabled debugging for the module within WHMCS and saw an error coming from the Mail Chimp sync plugin. Once that plugin was disabled everything was running smoothly again :slight_smile:

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