I'm getting this error on an avatar upload on my site. I've never gotten it before and nothing was changed recently for me to begin getting this error...
Warning: is_writable() [function.is-writable]: open_basedir restriction in effect. File(/) is not within the allowed path(s):
open_basedir setting is primarily used to prevent PHP scripts for a particular user from accessing files in another user's account. So usually, any files in your own account should be readable by your own scripts.
Example settings via
.htaccess if PHP runs as Apache module on a Linux system:
<DirectoryMatch "/home/sites/site81/"> php_admin_value open_basedir "/home/sites/site81/:/tmp/:/" </DirectoryMatch>
Modify the open_basedir settings in your hosting account and set them to none. Find the open_basedir setting given under 'PHP Settings' area of your Plesk/cPanel. Set it to 'none' from the dropdown given there. I have shown them in the Plesk panel picture.