Several days ago, I began to do a software update to see if there are any updates for the OS. I have done this many times over many years. When I began an OS software update several days ago, I got a mesage that said, more or less, that a secure connection could not be established or verified. My computer asked me if I wanted to proceed anyway. I did not proceed. I had never before gotten such a notice. A few days later, when I tried to make an SFTP connection completely unrelated to Apple, I got essentially the same notice and question. What causes these notices? Is this connection problem caused by a cracker, my computer, something wrong I did, the phone company, my ISP, or some other source? Can I identify the cause or stop the problem? Is there a security problem? If so, what's causing it?
The problem is stated above. Below, I give information which may be related.
In the Users and Groups preference panel which one sees when one creates a new user, there is no set of alternate images shown to the administrator. The new user automatically is given a log in image but the administrator is not shown a set of alternate images from which he may choose one. The images are in folders in root/Library/User Pictures but the images are not automatically shown to the administrator. When a new user is created, an image is automatically assigned to him. If one clicks that image, one sees three words: Defaults, Recents, Camera. Below those words, one sees "No Items". Two users have been given the same image. I think that this is evidence that my OS may be from a source other than Apple. I bought the computer with Lion. I downloaded Mountain Lion for free in the standard way over the Internet but it is conceivable that it did not really come from Apple, I suppose. I post this message because of the insecure connection problem which so far has occurred twice, once involving Mac OS software update.