Title: Reoccuring 'Call to undefined function' errors
Last modified: August 19, 2016

---

# Reoccuring 'Call to undefined function' errors

 *  [x Blazey](https://wordpress.org/support/users/x-blazey/)
 * (@x-blazey)
 * [15 years, 10 months ago](https://wordpress.org/support/topic/reoccuring-call-to-undefined-function-errors/)
 * I’m having a really strange problem, my blog will work fine for any period of
   time and then seemingly without reason will fail, and I’ll receive a call to 
   undefined function error.
 * Sometimes the blog itself will not work and it’ll complain about is_multisite,
   other times the blog still works but wp-login gives an error.
 * I can normally fix these issues by re-uploading the contents of wp-admin and 
   wp-includes, sometimes I need to re-upload the theme I’m using. But then things
   might work normally again for a while and then it fails again.
 * I’ve tried disabling plugins, I’ve tried a complete re-install of wordpress, 
   still the same problems. It seems like files are corrupting themselves on the
   server?

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

 *  [Darrell Schauss](https://wordpress.org/support/users/darrellonsite/)
 * (@darrellonsite)
 * [15 years, 10 months ago](https://wordpress.org/support/topic/reoccuring-call-to-undefined-function-errors/#post-1595759)
 * Is it just certain pages? Does it happen only on posts or pages?
 * have you also tried fresh copies of files in the root?
    [http://wordpress.org/support/topic/411446](http://wordpress.org/support/topic/411446)
 *  Thread Starter [x Blazey](https://wordpress.org/support/users/x-blazey/)
 * (@x-blazey)
 * [15 years, 10 months ago](https://wordpress.org/support/topic/reoccuring-call-to-undefined-function-errors/#post-1595760)
 * I have tried fresh copies in the root, normally that has no impact on the problem.
 * What I find is the home page will load fine, then I might navigate to a post 
   or a category for example and it’ll load fine but then I try to return to the
   home page and I find it’s not working and then everything is not working, really
   strange.
 * Had a look at that thread already, problem for me is those suggestions work in
   solving the problem but it continues to happen.

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

The topic ‘Reoccuring 'Call to undefined function' errors’ is closed to new replies.

## Tags

 * [problem](https://wordpress.org/support/topic-tag/problem/)
 * [undefined function](https://wordpress.org/support/topic-tag/undefined-function/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 2 replies
 * 2 participants
 * Last reply from: [x Blazey](https://wordpress.org/support/users/x-blazey/)
 * Last activity: [15 years, 10 months ago](https://wordpress.org/support/topic/reoccuring-call-to-undefined-function-errors/#post-1595760)
 * Status: not resolved

## Topics

### Topics with no replies

### Non-support topics

### Resolved topics

### Unresolved topics

### All topics