The 509 file extension is used to protect server, website transactions, logins, webmail, and SSL certificate connections. Choose the GlobalSign SSL certificate for the highest levels of strong security, reliability, and credibility for your website, corporate assets, and online brands.

If you're having trouble opening file 509, most of the time the only problem is that you don't have the correct application installed. Select one of the programs from the list and install it on your device. The operating system must automatically associate the 509 file format with the installed program. If not, right-click on the 509 files and select from the menu"Open with". Next, select the installed program and check the operation. Now all 509 files should open automatically in the program of your choice.