There are many ways for a script not to return valid HTTP headers in an intermittent way. The most obvious one is an intermittent restriction of some O/S level resource: open files, available RAM, etc.

Good point as usual hippo.
However, the examples you give would cause the other sites hosted on the same machine, including the test site for this domain, to give random error. They don't - or at least I have not experienced them. It is possible that they do as it is an intermittent problem but it seems unlikely that I would only notice it on one site and no others.

Are you still running on shared hosting? If so, the real error log is unlikely to be accessible to you...

Yes, it is on shared hosting with cPanel

According to the cPanel documentation, the error log I can see comes from /usr/local/apache/logs/error_log.

In reply to Re^2: Errors uncaught by CGI::Carp by Bod
in thread Errors uncaught by CGI::Carp by Bod

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