If you have encountered this specific filename, it likely belongs to one of the following categories:
Valve's anti-cheat system occasionally generates temporary or cached data files. These files are typically stored in game directories or the Steam folder to help identify unauthorized modifications to game files. 1595406539.vac
Use Microsoft Defender or Malwarebytes to perform a "Custom Scan" on the specific folder containing the file to ensure it isn't malicious. If you have encountered this specific filename, it
If it is in a temporary folder (like C:\Users\[User]\AppData\Local\Temp ), it is likely a leftover from a past installation or scan. If it is in C:\Windows\System32 and you did not put it there, use caution. If it is in a temporary folder (like
Many programs generate files named with a string of numbers (often a Unix timestamp) to ensure uniqueness. The number 1595406539 translates to Wednesday, July 22, 2020 , suggesting this file may have been created or timestamped on that specific date. Security and Maintenance
The software Virtual Audio Cable uses the .vac extension for some of its configuration or driver-related components. If you have audio routing software installed, this file may be a legitimate part of that toolkit.
, or did it appear after installing a specific game or audio tool ? How to Run a Full Scan Using Windows Security