Common server errors
In this article
Unexpected response / 403 error during saving the slider or slide
When you are seeing an unexpected response or 403 error message while you are trying to save, that means there is an issue at your server host. This error message is just a "catch all" message, meaning it doesn't tell you the cause of the problem, it just tells you the server stopped the process, but usually the problem is given by a ModSecurity setting, which doesn't allows you to save down certain datas. You should contact your server host, they have a log about what exactly is causing this problem and they should be able to help you resolve this issue.
500 Internal server error or blank page
500 errors are just "catch all" error messages, so they aren't telling you the cause, they are just telling you there is a problem and the server host has an error log, which contains the real error message. You should contact your server host and ask them for that log, also ask them to take a look at it, because a common server error is, that the
memory_limit is reached and in that case your server host would be able to increase that value.
If it won't be a server limitation, but an actual PHP error, from the error message you will see which file causes the problem and you could try to eliminate the given plugin from your website or contact their developers to fix the issue!
Learn how to make your site write out an error message.
Memory limit issue
If you see something like this in your error log:
Allowed memory size of 67108864 bytes exhaustedthen the problem is that your site reached your server's
memory_limit. You can check your hosting information by creating a file in your server, let's call it info.php, and put only this in it:
<?php phpinfo(); ?>
Then look at this file in your browser: http://example.org/info.php. Look for the
memory_limitvalue. Smart Slider 3 requires at least 64MB but your site might need much more, depending on the amount of extensions/plugins you have.
Contact your host and ask them to increase the memory limit of your server to ensure that it's big enough for your site's needs. If you're using WordPress you might be able to increase the
memory_limitby placing a code like this to your
Server hosts usually won't give you control to change the server values, so your code might won't do anything.
You have a plugin with an error
If you can't access your whole back-end, then you should connect your site via FTP, and rename the plugin folder names in your
wp-content/pluginsfolder one-by-one to see, if one of them solves your problem. If you only see the internal server error at the Smart Slider's page, then you can deactivate your plugins in your Plugins list too.
Bad .htaccess file
If you are editing your .htaccess file, so you're not using the default WordPress/Joomla one is used and you see this error, there is a chance, that you modified the .htaccess file wrongly. You should put back the original WordPress/Joomla given .htaccess file to see if your problem disappears that way.
Blank page maybe just after a number of slides
Go to Slider settings → Optimize and turn off the Optimize slide images if it's on. When you are using it with too big images, this is a resource heavy process, and probably your server's memory_limit has been reached. If this helps, either use smaller images in the future, or ask your server host to increase the memory_limit value of your website.
Messed up backend using AMPPS
First, try to make your site write out the error. That will give you the idea if you need to turn on some PHP extension, or increase some server setting.
Call to undefined function ctype_digit()
You should enable the ctype extension at AMPPS Application → PHP Tab → PHP Extension. Check ctype and Apply.
Slider doesn't work on Siteground hosting
This error is caused by SiteGround hosting, which replaces every http URL to https, and it causes a GSAP issue. You should go to your SiteGround settings and turn off
External Links Rewrite. SiteGround might have renamed this setting to
Slide settings doesn't loadIf the Slide settings page doesn't load for you, try making your site write out the error, and check the generated log file. If you see this error:
PHP Fatal error: Uncaught Error: Call to a member function getControlName() on null in /wp-content/plugins/nextend-smart-slider3-pro/Nextend/Framework/Form/AbstractField.php:108
Then your problem is related to a bug in older PHP versions. Contact your host and ask them to upgrade your PHP to at least PHP 7.3 and that should solve the problem.