Wordpress "The update cannot be installed because we will be unable to copy some files." error

Question

I am getting 

The update cannot be installed because we will be unable to copy some files. This is usually due to inconsistent file permissions.: wp-includes/js/mediaelement/bigplay.png, wp-includes/js/mediaelement/background.png, wp-includes/js/mediaelement/controls.png, wp-includes/images/admin-bar-sprite-2x.png, wp-includes/images/admin-bar-sprite.png, wp-includes/images/wpicons-2x.png

Installation Failed

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error while upgrading Wordpress Version. How can I fix this?=

Answer 1

First open putty with root user and run this

 

cd /home/WORDPRESS_SITE_FTP_USERNAME/public_html/wp-admin/images

 

and run this command, this command fix the files owner and group settings

 

chown WORDPRESS_SITE_FTP_USERNAME:WORDPRESS_SITE_FTP_USERNAME *.*

 

 

Answer 2

You must apply this command all files that you receive an error

 

For example 

for this : wp-includes/js/mediaelement/bigplay.png

cd /home/sitename/public_html/wp-includes/js/mediaelement

chown sitename:sitename *.*

Answer 3

If you get update error you can try to upgrade manually.