If you can't see the cookie consent toolbar in the frontend after the installation of the component, it's likely you have a javascript error/conflict on your website, most probably due to third-party extensions, multiple jQuery inclusion, old libraries, etc. this happens especially on the old Joomla 2.5 and websites with a lot of extensions installed.
If you are still on Joomla 2.5 and you have jQuery conflicts, you can try to install the plugin jQuery Easy that may help to fix this kind of issues https://simplifyyourweb.com/downloads/jquery-easy

It's strongly recommended that you open the browser console (F12) and inspect any javascript error. You can even try to disable the jQuery inclusion by the GDPR component especially if you are still using Joomla 2.5:


If you have enabled the feature to block third-party cookie resources take care to disable it in the cookie consent tab:

and disable all cookie categories having domains in the list of blocked ones, in this way you can test if the error was due to certain blocked resources:

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Additionally you may have installed an extension such as JCH Optimize or a specific template feature to merge all javascript files into a single file thus breaking scripts as in the image below:

If this is the case, you should disable such feature under settings of your template (such as T3, Gantry, Gavick Pro, etc) or configure the exclusion of files used by the GDPR component if possible, in order to preserve the execution ordering of scripts:
• cookieconsent.min.js
• init.js
• user.js
• jquery.fancybox.min.js
• checkbox.js

If you are using JCH Optimize or any other scripts having on-page Javascript errors, you can try to enable following settings:

If you are using JCH Optimize and the auto no conflict mode didn't work, you find below the correct configuration to be applied manually in order to preserve the correct execution order of scripts:

If you are unable to setup this configuration as an alternative you can disable the generic feature to merge all javascript files into a single one:

If you are using a template based on the T3 framework, you can try to add all files used by the GDPR component to the 'Exclude files' list: