Title: ao_speed_cachebuster FastCGi error
Last modified: April 13, 2019

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# ao_speed_cachebuster FastCGi error

 *  Resolved [virus021](https://wordpress.org/support/users/virus021/)
 * (@virus021)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/ao_speed_cachebuster-fastcgi-error/)
 * My server is logging following error:
    “error reading data from FastCGI server,
   referer: [https://www.personalsynthesis.com/?ao_speedup_cachebuster=93158&#8221](https://www.personalsynthesis.com/?ao_speedup_cachebuster=93158&#8221);
 * Is there a way to determine the source of the problem and solution. I’m not sure
   is this something that causes 500 error or not but I have seen this error in 
   logs
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fao_speed_cachebuster-fastcgi-error%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/ao_speed_cachebuster-fastcgi-error/#post-11424019)
 * the cachebuster requests are done by AO after the cache has been cleared to “
   warm up” the cache again, so have no impact on users or admins.
 * now why those requests would cause an error, that I don’t know; it essentially
   is a HTTP-request to your homepage with a parameter added to make sure the requests
   is not served by a page cache (which would not trigger the “warm cache”-routine).
 * hope this clarifies,
    frank
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [7 years, 1 month ago](https://wordpress.org/support/topic/ao_speed_cachebuster-fastcgi-error/#post-11469705)
 * Assuming resolved as no further feedback, but feel free to follow up here if 
   you still have questions! 🙂
 * frank

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘ao_speed_cachebuster FastCGi error’ is closed to new replies.

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 * 2 replies
 * 2 participants
 * Last reply from: [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * Last activity: [7 years, 1 month ago](https://wordpress.org/support/topic/ao_speed_cachebuster-fastcgi-error/#post-11469705)
 * Status: resolved