Right-click Part01 and select using your archive utility.
: The alphanumeric string is likely an MD5 or SHA-1 hash used to uniquely identify the content or ensure the integrity of the file during transfer. 99899ca6525f4586b64a0aef1b5a9049.part02.rar
: Files named with long hexadecimal strings are common in Usenet "nzb" feeds or automated backup systems. If the source is unknown, it is safer to delete it. How to Open It If you have the other parts of the set: Ensure Part01 is present. Right-click Part01 and select using your archive utility