I have a weird issue with Wordpress which I can't figure out how to solve. About a month ago I switched servers and carried my Wordpress files and databases from the old to the new. At the time, I had the old version of Wordpress, the one previous to the version that required php5 (because I didn't have it).
When I successfully moved everything, I upgraded my Wordpress to the latest version. I had some issues with some plugins (unfortunately, I can't remember which ones) which I didn't care that much, so I deleted the files from the plugin directory.
Everything seemed fine so I left it that way until I got an email one day that my blog was down. I went to have a look and all I saw was a blank page. Everything else in my server worked fine. There were no serious crash errors in my Apache log but I did notice that I did not enable php logging. So I made the appropriate changes to the php.ini, restarted Apache and it worked again.
Then, I few days later, the same thing happened. I just restarted Apache to see what would happen and it worked again. Apache error logs didn't show anything serious. Neither did Apache access logs or Ubuntu's system logs. For some reason though, I don't see any PHP log file even though I have set the log_errors = On and error_log to a full file path.
Any help? I don't even know where to start looking.