Let’s pull back the curtain on un.exe . What is it? Should you panic if you find it? And most importantly, how do you remove it? Unlike system files such as svchost.exe or explorer.exe , un.exe is not a legitimate Windows operating system file. In 99% of cases, finding this file running in your Task Manager is a red flag.
Open Task Manager ( Ctrl + Shift + Esc ), find un.exe , right-click, and select End Task . Do this before deleting the file.
Every so often, a filename starts circulating in IT support forums and Reddit threads that makes administrators break out in a cold sweat. The current contender for "Most Suspicious File of the Year" is a small, unassuming executable named un.exe .
Always check file properties. Right-click un.exe > Properties > Details. A legitimate file has a copyright, a company name, and a version number. Malware usually leaves these fields blank or fills them with gibberish.