How does unauthorized access typically occur, according to investigations?

Unauthorized access typically occurs through various methods, but the use of a trojan horse program remotely is a common and sophisticated approach. This type of malware is designed to deceive users by masquerading as legitimate software. Once installed on a victim's system, it can grant unauthorized access to the perpetrator, allowing them to control the system remotely, extract sensitive data, or perform various other malicious activities without the user's knowledge. This method capitalizes on the vulnerabilities in software or human errors, exemplifying the high-tech nature of modern unauthorized access.

In contrast, physical breaking and entering usually pertains to more traditional methods of unauthorized access that do not involve digital systems. Eyewitnesses play a role in investigations but are not a method of accessing systems. Direct physical access refers to gaining physical entry into a secure area, which is another means of gaining unauthorized access but is typically not as prevalent in the realm of digital crimes compared to methods that exploit technology, such as using trojan horse programs.