Slowness of the Prestashop based shop

  • Answered
Recently I have my shop (based on Prestashop acting very strange (I have 2 sites on the same server), it's very slow (page loading) and during my work on Prestashop Admin's Panel I often get this error:
A server error occurred while loading the tabs: some tabs could not be loaded.
Please try again by refreshing the page.
If you are still encountering this problem, please check your server logs or contact your hosting provider for assistance."

I don't know what does it mean and what can I do in order to prevent and resolve it?
This is not a JQuery issue, I'm taking about the first error, above it.
Thank you for your reply. It says:
"resource: net::ERR_CONNECTION_RESET…=105&action=Prices&updateproduct&ajax=1&rand=1468940489342&_=1468940488198 Failed to load" when I click on it it redirects to some page without any css I see only HTML.
here is screenshot of the console panel:

Sorry to hear you are having issues with your PrestaShop not loading tabs. We will need more information in order to be able to possibly assist. Follow the steps below to see what you come up with:

Turn on browser console

Reproduce the issue

In console you will see some "red errors"

Click on the error and turn on "response" section - What do you see?

Kindest Regards,
Scott M