Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm testing Zend Guard 5 to encode PHP source code, and have encoded a working website.

When I view the site on my server, I get an error page saying "Zend Optimizer not installed" and that it requires Optimizer 3.0 or newer.

I'm sure I have Zend Optimizer installed. We're running Zend Platform on that server, which includes Zend Optimizer v3.3.7. According to phpinfo() and according to the Zend Platform status screen it's installed and working. Somehow Zend Guard doesn't agree.

Any idea why Guard encoded files don't seem to use the available Optimizer?

share|improve this question
up vote 0 down vote accepted

Hmm, after experimenting more it appears this error only happens on quite complex legacy websites. I suppose Guard is less flexible about bad coding than PHP itself is.

Simpler, more cleanly coded PHP encodes nicely and runs fine.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.