I am in dire need of help for a mission critical site (live). Front UI shows the site but every time I put any page in edit mode it panics into an error page. I can access the dashboard and view site map and nav to pages but thats it.
** Whoops \ Exception \ ErrorException (E_WARNING) **
Use of undefined constant CACHE_LIFETIME - assumed ‘CACHE_LIFETIME’ (this will throw an Error in a future version of PHP)
I had installed a timeline_slider last week and it didn’t install, so I left it and came back to it a few days later. I then contacted the developer of the addon, to which he said, that the php version I was using was too old. So I logged into my hosting acc and changed from PHP5.6 to 7.3. After than, the Extend Concrete page to install the addon then appeared. So, I then went to install it and all looked OK. Then I went to the page I wanted to add it and got another page panic error. I was really frustrated then and decided to go back to PHP5.6, which then cause the whole site to go into page panic mode. I was frantic, and set it back to PHP7.3 and removed the stupid timelime_slider addon. Now I cannot even edit a single page on my site, but view site and get into the dashboard menus.
I checked the .htaccess file if there were any bad references, but all good.
I have looked in /Application/Blocks, but the folder is blank to see if any configuration.php file was around to rem our the cache_lifetime error.