Have you performed the usual trouble-shooting routines (trashing prefs by keeping command-alt-shift/ctrl-alt-shift pressed while starting Photoshop, 3rd party plug-ins deactivation, system maintenance, font validation, etc.)?
I tend to think that your AI install has messed with some shared libraries e.g. for PDF handling. This might also have some ill effect on Acrobat/ Adobe Reader. in that case, you should consider running the Creative Suite Cleaner Tool and reinstall everything from scratch and only then start applying updates to all the programs.
for c.pfaffenbichlertried: I tried ctrl+alt+shift and deactivating plugins, no effect at all.
for Mylenium: I do not have PS CS5 "installed" - I downloaded its files on internet because I lost my DVDs and just extracted it already installed. As the result, the Cleaner Tool doesnt recognize there is PS on the machine.
However, I uninstalled Illustrator - and it looks like PS works. Strange, but I want both installed and working
I downloaded its files on internet because I lost my DVDs and just extracted it already installed.
That might actually be the problem. It's possible your "portable" PS contains outdated path and configuration info. Therefore you might wanna try and download PS CS5 again as per these instructions and reinstall properly. This might take care of the issue and allow to use AI without problems while keeping PS intact.
>> I downloaded its files on internet because I lost my DVDs and just extracted it already installed.
Then you're missing a lot of files and most likely just added malware to your system.
Many of those "portable" copies of Photoshop are distributed by organized crime groups that use it as a trojan horse to add malware to your system.
Plus you're running 12.0.0 instead of the current 12.0.4.