The FastCGI process exited unexpectedly

[snake]

suddenly we cannot access our WHMCS Admin, we get the error.

 

 

HTTP Error 500.0 - Internal Server Error

C:\Program Files (x86)\PHP\v5.3\php-cgi.exe - The FastCGI process exited unexpectedly

 

we are running windows 2008 R2, IIS 7.5

 

there is nothing more useful in the IIS logs or the php logs, after many hours of Googling it seems this is a nightmare to try and determine the cause when a PHP app causes fastcgi to crash as there is no debug info anywhere.

I have used the failed request tracing and that simply tells me that PHP-CGI was the cause, nothing more.

 

Nothing has changed on the server, PHP has *NOT* been updated, and it is working fine for other sites, only the WHMCS admin is causing this error.

 

Prior to this we were getting the following error from WHMCS, so I think this must be related. I had to increate PHP memory limit to 512mb to get rid of this error.

 

Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 261904 bytes) in D:\path to site\whmcs\includes\dbfunctions.php on line 0

[snake]

ok I switched off fastcgi and am using php-cgi.exe directly, which gives me a different error.

 

HTTP Error 502.2 - Bad Gateway

The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are "".

[snake]

For the benefit of anyone else having this issue I did solve it.

A couple of the WHMCS tables had become corrupted, I scanned the database with MYSQLCHECK to find this, and repaired the tables.

 

I find it quite astounding that WHMCS doesn't have any error handling to deal with stuff like this, especially when your talking about billing software which is critical to everyone's business. It really should handle errors better and tell you what caused it, rather than simply crash PHP and cause a server error.

 

Unfortunately WHMCS support have absolutely no idea where to start or what to do when WHMCS breaks like this, so your pretty much left up sh*t creek.