PS CS5 btw.
Basically the upgrade to Yosemite damages the Photoshop CS5 installation
The answer is to reinstall CS5.
Thank you for your help on this.
All seemed to go well, after I uninstalled and re-instaslled PS. However, I found that it would not accept my serial number any more and went into the 30 day trial period, which has now expired. I need somehow to get someone at Adobe to help me fix this. Not sure how, I have emailed and phoned, but no response.
There are two stages. If your serial number is good, you get a green checkmark.
If you copied it incorrectly, you would see a red x. It's easy to do with a 24 digit number.
So let's say you got a green checkmark, then next you would activate it. If you exceed your activations, you will get a message, and if Adobe thought it was being passed around they would retire it.
What reason did they give you?