I'm not able to save my slider anymore. I need to remove the first slide but I can't due to an error I never got before:
It seems there is a server issue that prevented LayerSlider from saving your work. Please, try to temporary disable themes/plugins, or contact with your hosting provider. Your HTTP server thrown the following error: Not Found
I've tried everything (log files, disabled plugins one by one...) but could not pinpoint the error. I don't know what's happening nor do I know how to fix this. Can you help? I can provide wordpress credentials if needed.
Judging from the error message this is a typical web server issue. You will need to contact your hosting provider with this and show them the error message. They should know what's wrong exactly and make the necessary changes.
Potential problems could be the limitation of open connections or limitation of the total outgoing traffic bandwidth. It's also recommended to check on the .htaccess files to see if there are any custom changes that could cause this.
I have exactly the same problem and I contacted my hosting provider and showed them the error message. They had absolutely no idea of what changes were necessary.
It would be helpful if you posted the server requirements to run your plug-in so we could forward it to our provider. Otherwise you blame the provider, and the provider blames you, and we paid for nothing a piece of software we cannot use.
I tend to agree with frangagn. My hosting provider will likely tell me to ask the plugin provider to fix this.
The error appeared when I updated to the last version of Layer Slider. Is a next released planned soon to fix this issue?
In the meantime, I'm promoting obsolete info on my website, and I can't promote an upcoming show on my home page. This is really annoying.
As the problem is most likely related to a server configuration issue, we cannot fix it from our end unforunately. Only your hosting provider has the necessary information and tools available to solve this.
As I've mentioned in frangagn's ticket, there isn't any special requirement for the plugin. Other than the default requirements that WordPress also needs, only PHP 5.3 (or newer) and the few exetensions that you can see in the System Status are needed.
Your hosting should look into any limitation they might have, like the limitation of open connections, limitation of the total outgoing traffic bandwidth, firewall or custom routing/filtering. Custom rules and changes in the .htaccess files could also cause this.
In the meantime you could also try to look for an incompatibility issue on your installation to see if there is an interfering with a 3rd party item, by temporary disabling other plugins and switching to a default theme.
It this can help others: I asked my hosting provider for help. They disabled a few mod_security rules saying it should fix the issue, and it actually did, I was able to save my slider.
I asked them if there was a way for me to do it myself the next time Wordpress updates itself automatically, with a htaccess directive for example, waiting for their reply. Worst case scenario, next time I stumble upon the same error, I will know what to do and what to tell the support team of my hosting provider.
Thank you for the feedback, glad you could solve the problem. If you need further assistance please let us know.