I'm trying to update languages for CS5.5 7.5.3 Mac. Specifically I need Japanese. When downloading the update from this page:
The AdobePatchInstaller shows the following error message:
"AdobePatchInstaller" is damaged and can't be opened. You should eject the disk image.
IF Mac El Capitan (or newer Sierra operating system) read below
CS6 and earlier programs have not been tested and will not be updated to run on Mac El Capitan
-which means that you try to use CS6 and earlier at YOUR risk of having problems
-you may get CS6 and earlier programs to install and run, or you may not (some do, some don't)
Install CS5 on Mac 10.11 https://forums.adobe.com/thread/2003455 may help (also for other than CS5)
-also a TEMPORARY security change https://forums.adobe.com/thread/2039319
-and more on gatekeeper https://support.apple.com/en-au/HT202491
Besides what John has to say, try a different browser.