PC.net

.cer

File Type Internet Security Certificate IconInternet Security Certificate
File Format Standard
Usage Referenced by an application; not meant to be opened manually
Rank ★ ★ ★  Common
Description

Security file provided by a third party such as VeriSign or Thwate that confirms the authenticity of a Web site; installed on a Web server (such as Apache or Windows Advanced Server) to authenticate the validity of a certain website hosted on the server; represented by a lock icon near the edge of a browser window when accessing a secure site (beginning with "https://").

The information from a secure certificate can be viewed by double-clicking the lock icon located near the bottom of a browser window in Internet Explorer or Firefox; to view the certificate information in Safari, click the lock icon near the top-right corner of a browser window.

Open With
Windows

IconMicrosoft Internet Explorer

IconMozilla Firefox

IconOther Web browser

macOS

IconApple Safari

IconMozilla Firefox

IconAdobe Reader

Unix

IconMozilla Firefox

IconAdobe Reader

Updated 2007
Information from the PC File Extensions Reference
https://pc.net/extensions/file/cer
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