Which symptom indicates a Trojan infection on a computer?

A Trojan infection on a computer is often characterized by unexpected system behavior. This can manifest in various ways, such as unusual application launches, unauthorized changes to system settings, or the presence of unfamiliar files and processes running in the background. Trojans are designed to deceive users and create backdoors for potential malicious activities, leading to actions that the user did not intend or consent to. As a result, recognizing unexpected behaviors is crucial for identifying the presence of this type of malware.

While increased network traffic, frequent system crashes, and slow performance can also indicate malware infections or other system issues, they are not specifically tied to Trojan infections. Increased network traffic might suggest a different type of malware, like a worm. Frequent crashes could stem from software incompatibility or hardware issues, and slow performance can result from various factors, including insufficient system resources or legitimate software running in the background. Therefore, when diagnosing a Trojan infection, the primary indicator to look for is indeed the unexpected system behavior that it often causes.