1] After installing wordpress and various plugins I tried to change Permalink Structure from Default [http://www.sitename.com/blog/?p=123] to
Custom structure: /%postname%/
However, I am getting following error message on my blog:
Fatal error: Call to undefined function: user_trailingslashit() in path-to-site/wp-includes/category-template.php on line 38
2] .htaccess file has been uploaded to blog directory and has write permission enabled.
3] If i switch back from Custom structure: /%postname%/ to
Default structure [http://www.sitename.com/blog/?p=123]
the error disappears.