Error uploading files bigger than 58 MB

Some ideas:

• You should check your php info, just to verify your upload settings (<?php phpinfo();?>)

• You could try a single install, to see if you have the same problems as with multisite.

• You should also try some 3rd party upload script yourself.

• In /wp-includes/script-loader.php I found these lines:

  // common bits for both uploaders
  $max_upload_size = ( (int) ( $max_up = @ini_get('upload_max_filesize') ) < (int) ( $max_post = @ini_get('post_max_size') ) ) ? $max_up : $max_post;
  
  if ( empty($max_upload_size) )
          $max_upload_size = __('not configured');
  

so it is using the minimum of upload_max_filesize and post_max_size. It looks though you have these variables as set as 192MB > 58MB.