Article: You'll be checking for any available updates for the Adobe Camera Raw plugin. This plugin includes support for CR2 files, and is updated when newer camera models are released. If you're using Photoshop CC, select "Updates..." instead. This will look for any updates available online for Photoshop and its plugins, including the Camera Raw plugin. The Camera Raw plugin adds support for various raw files, including the CR2 format. If the Camera Raw plugin has an update available, it will be listed in the Adobe Application Manager list. Select it and click the "Update" button. If the automatic update process fails, you can download the latest Adobe Camera Raw (ACR) update available for your version of Photoshop. You can see the version of Photoshop you're running in the program's title bar. Earlier versions do not support later ACR releases. Follow the links below and run the installer to install the plugin: Adobe CS4 - ACR 5.7 (https://www.adobe.com/support/downloads/thankyou.jsp?ftpID=4683&fileID=4375) Adobe CS5 - ACR 6.7 (https://www.adobe.com/support/downloads/thankyou.jsp?ftpID=5603&fileID=5613) Adobe CS6 - ACR 9.1.1 (https://helpx.adobe.com/camera-raw/kb/camera-raw-plug-in-installer.html) Adobe CC 2014/15 - 9.7 (https://helpx.adobe.com/camera-raw/kb/camera-raw-plug-in-installer.html) After installing the latest version of ACR for Photoshop, try opening the CR2 file again. If the ACR update included support for your camera, the CR2 file will open in a Camera Raw window. If you're using an older version of Photoshop with an older version of ACR, you may not be able to open photos taken with cameras released after that ACR version. For example, if you have a Canon EOS 5D Mark III, you'll need ACR 7.1 or later, which isn't available in CS4 or CS5. If this is the case, see the next section for conversion instructions.

What is a summary?
Open Photoshop. Click the "Help" menu and select "Check for Updates." Install any available Camera Raw updates. Install the latest Camera Raw update manually if the update fails. Attempt to open the CR2 file in Photoshop again.