Unfortunately some web hosts are configured in a manner that will not allow external communication to our license servers, preventing you from verifying your license key to get automatic updates and add-on package installation. As this is a known problem, we have made accommodations for it as best we can offer in our plugin.
Getting rid of the "License key is missing" Notification Message
If you are receiving a Connection Error message below your license key field, you can still input your license key and save it. Just enter the license key in the field and click the Update Options button at the bottom of the form. This will save your license key, but not validate it with our servers, eliminating the "License key is missing" notification message.
You will still not be able to receive updates or install add-ons automatically until you get the communication issue resolved with your web host. If you don't care about automatic updates and add-on installation, this may be enough for you, but you will need to manually download updated copies of the plugin and manually install the new version on your site yourself. We do not send out any messaging about new releases outside of updates here in the digital-telepathy support forums and the in control panel WordPress plugin update notification, so be sure to check for updates every once in a while on your digital-telepathy dashboard at http://www.slidedeck.com/login.
Fixing the problem with your web host
This problem can exist for numerous reasons ranging from firewall restrictions to PHP not being configured with the right server-side communication libraries. We recommend that you please communicate with your web host and ask that the following actions be taken for proper communication with our license and update servers:
Make sure update.slidedeck.com and its IP is whitelisted
To protect their users, web hosts are usually very restrictive about who they allow their servers to communicate with. A web host will have a firewall service in place that will restrict external server access only to known white listed IPs and domains. Request that your web host add both update.slidedeck.com and its IP address of 184.108.40.206 to their firewall white list. This URL is accessed via standard HTTP (port 80) and HTTPS (port 443) ports.
Make sure CURL is enabled
When attempting to communicate with external servers, WordPress will cycle through multiple methods of doing so until it can find a technology that it has access to. CURL is the first in the list, so make sure your web host has CURL enabled for PHP.
Make sure allow_url_fopen is enabled
Next to CURL is PHP's streaming API that uses the PHP fopen() command to communicate externally. If CURL is not enabled, WordPress will attempt to use this technology to communicate externally. Make sure that the PHP option allow_url_fopen is enabled.
If you still have problems
If you're still having problems, please open a support ticket with us and we'll see if we can help you resolve the problem. Before contacting us though, we recommend that you please download our dt Connection Diagnostics plugin to get some more information about your server so we can see what might be going wrong:
- Download the dt Connection Diagnostics plugin at https://www.dropbox.com/s/s36w4mnp2d49xo1/dt-connection-diagnostics.zip
- Install the plugin (WordPress Codex: Manually Installing Plugins)
- Activate the plugin
- Go to Settings -> dt Connection Diagnostics to run the diagnostic
- Copy and paste as much of the information output as you feel comfortable into a new support ticket regarding the issue