Title: Call to undefined function wp()
Last modified: August 18, 2016

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# Call to undefined function wp()

 *  [digriz60](https://wordpress.org/support/users/digriz60/)
 * (@digriz60)
 * [20 years, 4 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp/)
 * I am testing a newly unzipped install of WP 2. I’m running IIS and installed 
   the PHP package. I’ve already modified the wp-config file with my server logons.
   When I point to localhost/index.php I get the error
 * Fatal Error: Call to Undefined Function WP()
 * Any ideas? Is it not finding a linked php file?
 * TIA,
 * Steve

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

 *  [Kafkaesqui](https://wordpress.org/support/users/kafkaesqui/)
 * (@kafkaesqui)
 * [20 years, 4 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp/#post-333531)
 * Do you have a wp-includes/ directory? Are the files classes.php and functions.
   php located there, and are not corrupted or zero-byte in size?
 *  [macrocosim](https://wordpress.org/support/users/macrocosim/)
 * (@macrocosim)
 * [20 years, 4 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp/#post-333905)
 * OMG Thanks so much … I have been digging for hours trying to find the reason 
   I was getting this same error problem. For some reason my cach.php was zero-byte’s…
   WTF causes that? It turned my “famous 5 min instillation” into three hours of
   hell! lol …. anyways thanks for the tip … I hope others are able to find this
   post as there is no refferenc to this issue in ANY of the wordpress documentation.

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

The topic ‘Call to undefined function wp()’ is closed to new replies.

 * In: [Installing WordPress](https://wordpress.org/support/forum/installation/)
 * 2 replies
 * 3 participants
 * Last reply from: [macrocosim](https://wordpress.org/support/users/macrocosim/)
 * Last activity: [20 years, 4 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp/#post-333905)
 * Status: not resolved

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