Where does this error message come from?
I always get a SQL error in tikidblib line ~125, but I can't find the location of the query.
Yes, all DB queries must go by there. Use text search tools like grep or better: Install XDebug
, edit your php.ini like described in XDebug's installation manual, restart your webserver and you'll see a stack trace every time a error occurs.
Warning: Smarty error: unable to read resource: "error.tpl" in /var/www/html/HEAD/lib/smarty/Smarty.class.php on line 1144
Should be solved by clearing tiki/templates_c/
Allowed memory size of xxx bytes exhausted (tried to allocate...
Tiki needs lots of memory. 8MB is the minimum, 12MB should be enough for starting and 16MB should be comfortable during a good time. This site runs with 24MB. In php.ini just change the value of memory_limit (and restart Apache).
Warning: ob_start(): output handler 'ob_gzhandler' cannot be used after 'URL-Rewriter' in ...
Disable Use gzipped output from Admin General. This happens because Apache already compresses the output due to your php.ini settings. Use one or the other.