I get this same error on the current version running on WampServer. Usual thing I'm trying to learn Php and it doesn't work so fixing it using Php it somewhat of a challenge. That said the inital problem I have with the solution is that there is no index.php in p4a. Assuming that it is now called p4a.php I added the above code there and it has no effect. Can anyone suggest a solution please.
Mp4 Joiner Malware Link