Files with 509 extension are associated with internet security of your server, web sites etc.
Software that open 509 file
509 file extension - Internet security certificate
What is 509 file? How to open 509 files?
The 509 file extension is used to secure your server, web site transactions, logins, webmail and connections with an SSL Certificate. Choose GlobalSign SSL Certificates for the highest levels of strong security, confidence and trust in your web site, corporate assets and online brand.
Mime: application/x-x509-ca-cert
List of recommended software applications associated to the .509 file extension
Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open 509 file, edit 509 file, convert 509 file, view 509 file, play 509 file etc. (if exist software for corresponding action in File-Extensions.org's database).
Unspecified and all other actions for computer programs working with 509 file - Internet security certificate
Click on the software link for more information about Opera browser. Opera browser uses 509 file type for its internal purposes and/or also by different way than common edit or open file actions (eg. to install/execute/support an application itself, to store application or user data, configure program etc.).