title: Apache error "error AH00428: Parent: child process 11144 exited with status 255" with PHP 7
body: <p>I am running Wamp server 3.0.6 64 bits with Apache 2.4.23 - MySQL 5.7.14</p>
  
  <p>When I use PHP 5.6.25 everything works fine, I have no problem.</p>
  
  <p>But when I use PHP 7.0.10 I get following errors on Apache log when I stress a little the application (several PHP request running at the same time and requesting mysql database through PDO connection)</p>
  
  <pre><code>[Wed Jul 26 18:55:25.459433 2017] [mpm_winnt:notice] [pid 11352:tid 616] AH00428: Parent: child process 5560 exited with status 255 -- Restarting.
  [Wed Jul 26 18:55:25.613195 2017] [auth_digest:notice] [pid 11352:tid 616] AH01757: generating secret for digest authentication ...
  [Wed Jul 26 18:55:25.703752 2017] [mpm_winnt:notice] [pid 11352:tid 616] AH00455: Apache/2.4.23 (Win64) PHP/7.0.10 configured -- resuming normal operations
  [Wed Jul 26 18:55:25.703752 2017] [mpm_winnt:notice] [pid 11352:tid 616] AH00456: Apache Lounge VC14 Server built: Jul  1 2016 11:43:51
  [Wed Jul 26 18:55:25.703752 2017] [core:notice] [pid 11352:tid 616] AH00094: Command line: 'c:\\wamp64\\bin\\apache\\apache2.4.23\\bin\\httpd.exe -d C:/wamp64/bin/apache/apache2.4.23'
  [Wed Jul 26 18:55:25.703752 2017] [mpm_winnt:notice] [pid 11352:tid 616] AH00418: Parent: Created child process 12680
  [Wed Jul 26 18:55:27.304382 2017] [auth_digest:notice] [pid 12680:tid 648] AH01757: generating secret for digest authentication ...
  [Wed Jul 26 18:55:27.324432 2017] [mpm_winnt:notice] [pid 12680:tid 648] AH00354: Child: Starting 64 worker threads.
  </code></pre>
  
  <p>I saw some posts with similar error on stackoverflow, but no answer solve my problem and there is no mention of PHP version that would cause that error.</p>
  
  <p>Did anyone meet / solve that problem?</p>
  
  <p>Thank you!</p>