500 - Internal server error (Joomla)
- 500 - Internal server error message at any point in your website.
500 errors are just "catch all" error messages, so they aren't telling you the cause, they are just telling you there is a problem and the server host has an error log, which contains the real error message. You should contact your server host and ask them for that log, also ask them to take a look at it, because a common server error is, that the memory_limit is reached and in that case your server host would be able to increase that value.
If it won't be a server limitation, but an actual PHP error, from the error message you will see which file causes the problem and you could try to eliminate the given extension from your website or contact their developers to fix the issue.
Misconfigured .htaccess file
If you are editing your .htaccess file, so not the default Joomla one is used and you see this error, there is a chance, that you modified the .htaccess file wrongly. Possible solution:
Try to comment the Options +FollowSymLinks:
You can also try to remove the comment (# sign) from the # RewriteBase / code:
If your website is in a subfolder on your server, for example you can reach it here: http://mywebsite.com/subsite, then try out this at the RewriteBase: