To give you a more specific guide, I need to know a little more about where you found this:
If you did not personally download this file from a known source, . dob.80689.rar
Did you or receive it in an email ? Are you working on a construction or renovation project ? Are you seeing an error message when you try to open it? To give you a more specific guide, I
: A free, open-source alternative that handles almost all archive types. dob.80689.rar
In the context of New York City construction and permits, "DOB" refers to the Department of Buildings .
If this file is indeed from a project filing, you are likely to find:
: .rar files are frequently used to hide malicious executables (.exe, .scr, .vbs).