150:30 error updated License repair guide for CS3, CS4, Acrobat 8-9 and Photoshop Elements 8
Error 150:30 message "License for this product has stopped working" is displayed when Photoshop CS4 will not open because activation has been broken, usually on restore from backup such as MacOS Time Machine or migration from another computer. This fix is for CS3, CS4, Acrobat 8 and 9 products and Photoshop Elements 8.
Since my old guide was lost in the transfer to the new forum software, I've updated and reposted it.
A simple fix would be to reinstall CS4, but given that installers have been removed from Adobe servers, and users likely lost track of their install media, this may not be possible. The other answer is to download the License Recovery Repair Tool from Adobe. This saves a reinstall and having to re-apply all updates.
If the error is in Windows, running the repair tool is simple, it is a Windows executable.
Mac OS has a problem. Their repair app works only for OSX 10.6 which is easy to run. OSX 10.7 and above is a bit more complicated. It comes with a python script--LicenseRecover.py which can only be run on the MacOS Utility: Terminal.
Many users are not familar with this procedure, so I hope to break it down into easy to understand parts with screenshots to explain it. Go over the instructions until you understand them before attempting the repair.
Before I start, a warning that CS4 and similar Adobe progams are 32-bit apps and will not run in MacOS 10.15 Catalina which now allows only 64-bit apps. Don't upgrade if you want to keep CS4.

