What
exactly did you restore and how? When I look at the source code of your restored site's page I see
<jdoc:include type="head" /><link href="https://www.akeeba.com/templates/ol_chranet/images/favicon.ico" rel="shortcut icon" type="image/x-icon" /><style type="text/css">
That's something I would expect to see in a Joomla! template's index.php file. However, that is NOT a file that is served directly to the browser. It is a file that needs to go through Joomla! itself and transformed into something a browser can understand.
From the looks of it, you have copied the index.php file of your template i.e. templates/
YOUR_TEMPLATE_NAME_HERE/index.php into the main site's folder. This will not work and it will most definitely break your site, exactly as observed.
I also don't know why would anyone hard-code the menu of their site inside the site's template, completely beating the purpose of having a content management system, but that's irrelevant to your issue. I just needed to preemptively explain why you see "the site's menu" which mislead both of you into believing that you have some site display issue after restoration. No, the problem is that the wrong index.php file was
manually copied to the site's root.
If that's all the backups you've got from that site you're stuck between a rock and a hard place: your backup was taken after someone manually copied the wrong file around breaking the site's frontend, therefore you have a backup with a broken site. A simple way to fix that is extracting Joomla! 3.8.0 on top of the restored site
and delete the installation directory before trying to access your site. Doing so will overwrite all Joomla! core files with what they should be and, hopefully, let your site work again.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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