I'm a Mac user and I've recently upgraded my OS to Yosemite so I had to re-install my CS5 from a CD but it's pretty outdated. So now when I try to uptade CS5 it will download all the updates as if it was working and after reaching 100% a message appear sa

problems to install CS5 updates on OS 10.10.2 Yosemite

This one is very easy to explain—and solve.
The Adobe updater in CS5 and earlier versions of Photoshop was and remains a totally useless, unreliable piece of cr@p.  The hapless Adobe installer and updater team in India did not get their act together until version CS6, then went back to their usual incompetence with Photoshop CC and CC2014.
There's absolutely nothing wrong with your Photoshop installation and you are doing nothing wrong yourself.
What you're going to have to do, is locate, download and install the update you need yourself, following the instructions on the download page to the letter.
for Mac:
Adobe - Photoshop : For Macintosh : Adobe Photoshop 12.0.4 update for Adobe Photoshop CS5
Of course, ignore the idiotic recommendation that appears there to try to use Help > Updates.  We already know that doesn't work.

Similar Messages

Maybe you are looking for