At the beginning of the episode, Grant MacLaren is relieving stress at the FBI range. He is firing an FBI standard issue Glock Model 22. Several times Grant is shown manually operating the slide to load a bullet into the chamber of the firearm. However, this particular pistol is a semi-automatic meaning that when the last bullet is fired, the slide locks to the rear. This allows the shooter to release the empty magazine and enter a loaded magazine into the pistol, release the slide lock, chambering a new round and continue shooting. There is no reason a trained shooter would empty a magazine, force the slide forward, load a new magazine and then chamber a new round. It is not only inefficient but also a bad habit to develop that could potentially manifest in a firefight.
Simon's computer flashes up a warning that his self-signed certificate has been revoked by SSL. SSL, or secure sockets layer, is a technology and specification, not an organization or application. A self-signed certificate means the user has opted to not use a certifying third party to validate their identity, so the only person that could have revoked the certificate is Simon.