Title: Fatal Errors
Last modified: August 22, 2016

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# Fatal Errors

 *  [squire2k](https://wordpress.org/support/users/squire2k/)
 * (@squire2k)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/fatal-errors-28/)
 * Hi – We are using wordpress 4.1.1 with Yoast 1.7.4 – when we activate yoast we
   get the following message
 * **Fatal error: Class ‘WPSEO_OpenGraph’ not found in ….. on line 275**
 * and if we then disable the social OG (which we do need)
 * we then get
 * **Fatal error: Class ‘WPSEO_Replace_Vars’ not found in ….. on line171**
 * Does anyone know why this could be happening or how we can resolve
 * Many thanks in advance
 * [https://wordpress.org/plugins/wordpress-seo/](https://wordpress.org/plugins/wordpress-seo/)

Viewing 1 replies (of 1 total)

 *  Thread Starter [squire2k](https://wordpress.org/support/users/squire2k/)
 * (@squire2k)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/fatal-errors-28/#post-5894855)
 * just a bump – would be great to get this resolved

Viewing 1 replies (of 1 total)

The topic ‘Fatal Errors’ is closed to new replies.

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 * 1 reply
 * 1 participant
 * Last reply from: [squire2k](https://wordpress.org/support/users/squire2k/)
 * Last activity: [11 years, 2 months ago](https://wordpress.org/support/topic/fatal-errors-28/#post-5894855)
 * Status: not resolved