List some common signs of malware infection.
Common signs of malware infection include frequent pop-up windows prompting users to visit websites or download software. Users may also notice changes to the default homepage of their web browser or observe that mass emails are being sent from their email account without their knowledge.
Another significant sign is an unusually slow computer that experiences frequent crashes. Furthermore, unknown programs may startup when the computer is turned on, or existing programs might open and close automatically without user intervention.
Other indicators include a sudden lack of storage space and the appearance of random messages, sounds, or music. Lastly, programs or files may appear or disappear without the user's knowledge.
Explanation
The answer is derived directly from the list provided in the textbook under the section '12.2.9 Combating Malware'. It lists specific behavioral changes and system issues such as pop-ups, homepage changes, mass emails, performance slowdowns, and unauthorized file modifications as key indicators of an infection.