get_blog_details

When I go to Dashboard >My Sites I get the following error:

Fatal error: Call to undefined function get_blog_details() in /home/xxxxx/xxxxx/www/wp-includes/ms-functions.php on line 63

Using the following command, I see the function listed several times but I don’t see it defined anywhere:

grep -r get_blog_details *

Now then, I can’t program php,but I can find and do minor hacks so I need non-technical info. Where is this function defined? What file? I want to be sure I have that file at my site.