Whenever you encounter a specific .rar file from an unverified source, you must exercise extreme caution. Digital archives are one of the most common delivery methods for malware.
Many sites hosting these "packs" will bombard you with pop-ups claiming your system is infected, attempting to trick you into downloading "repair" software.
If you are determined to explore the contents of a file like "755 - PacksVirales.com .rar," follow these best practices: