I have a joomla site and I tried to install Akeeba Backup component but it was not installed due to post_max_size limit. After that I have tried to install it via directory option in joomla and changed the permissions of "tmp" folder. but the path was not correct and the component was not installed.
Now my admin panel is working fine but front end gives 500 internal server error. I have not changed .htaccess file it is the same. And if I put any other file like "index.html" or any other file I can access it. But joomla is not working.
What could be the problem?
Sounds like you have either an incorrect /tmp file path or the incorrect permissions. Is this a live or local server? Can you replicate the issue locally?
Turn on error reporting in your admin area and see if there are any errors displayed.
In admin area check System Information > Directory Permissions and make sure status is writeable.
Check the permissions of all of your files/directories - especially the /tmp.
There is additional info here
Hope this helps.