There are some issues I can think of:
1.
Missing files from the backup. Please extract your backup locally (use Akeeba eXtract Wizard) and see if there are any files missing when compared with the site you backed up from.
2.
Wrong permissions. Make sure that the permissions of your directories are at least 0755 and the permissions of your files at least 0644. Otherwise, Javascript won't load, with the consequences you described.
3.
A Javascript blocker. If you have NoScript or a similar extension installed on your browser, it is possible that it is preventing Javascript on your live site to run. In this case you will observe what you reported. Just disable the Javascript blocker for your site.
4.
A freak coincidence. This is my favourite, as it causes a lot of hair pulling! In some occasions, the site worked properly on a local dev server but when put online, everything broke. Why? PHP version differences caused something (e.g. a plugin) to misbehave and take everything down with it. If all of the above failed, please send me a
Personal Message (I am user "nicholas") with the following information so that I can help:
- URL to your live site
- Super Administrator username/password
- FTP connection information
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!