Title: Failed to read FastCGI header
Last modified: January 2, 2018

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# Failed to read FastCGI header

 *  [patbell101](https://wordpress.org/support/users/patbell101/)
 * (@patbell101)
 * [8 years, 4 months ago](https://wordpress.org/support/topic/failed-to-read-fastcgi-header-3/)
 * My site keeps generating error 503 screens. The error log says Failed to read
   FastCGI header which my host says is caused by fault php and recommends isolatig
   the errant plugin. MailPoet active gives me a CPU usage of between 65 to 75%,
   inactive my cpu is 40%. Disabling any of the other plugins makes no significant
   change

Viewing 1 replies (of 1 total)

 *  [aberry](https://wordpress.org/support/users/aberry/)
 * (@aberry)
 * [8 years, 4 months ago](https://wordpress.org/support/topic/failed-to-read-fastcgi-header-3/#post-9827231)
 * Hi Patbell,
 * I hadn’t connected the dots – I was getting 503 screens before I got the 500 
   screen I complained about this morning.
 * I have disabled MailPoet for the time being as I suspect that it is causing the
   problems and needs looking at.

Viewing 1 replies (of 1 total)

The topic ‘Failed to read FastCGI header’ is closed to new replies.

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 * 1 reply
 * 2 participants
 * Last reply from: [aberry](https://wordpress.org/support/users/aberry/)
 * Last activity: [8 years, 4 months ago](https://wordpress.org/support/topic/failed-to-read-fastcgi-header-3/#post-9827231)
 * Status: not resolved