Hello @BenjaminCoast
I believe that you may have some custom menu items.
Take a look at your code and see if you have been using menu_exists().
There are some important coding techniques when creating custom menu items.
Whenever you want to add or remove menu items, it is wise to use the menu_exists() function.
If you don’t use it to see if a menu item has already been created, you could add it multiple times.
To prevent this, you want to ensure it does not already exist.
When you want to remove a menu item, you want to ensure that it does exist.
The menu_delete should be inside a condition that first tests for the existence of said menu item.
Using this technique eliminates all the error messages about trying to delete menu items that don’t exist.
I would recommend searching your custom directories for an .acl file that is calling the custom menu. A simple test would be to rename the custom menu as .xxx and see if you can work with the out of the box menu items.
If this then resolves the errors, you know you need to do some work with your customised menu's.
I hope this is of help.
Could I please ask also, if any posts help you resolve the issue - please mark it as 'Accept as Solution'