I use the Admin Menu module for my projects. In my Drupal 7 and Pressflow 7 instances, it randomly shows only some menu items.
At first, I thought I could correct this by clearing menu cache. When I went to the front page, I once again got the corrupted menu.
How do I solve this error, permanently?
I disabled menu caching with
drush vset admin_menu_cache_client 0 as a workaround.
(I am still testing this issue with the menu cache enabled.)
I removed BOM from *.js files as suggested in this answer.