allelujah !

merci paparadezy pour ton conseil mais j avais deja essayé le mode administrateur

j ai trouvé la solution ailleurs :

So when you put the disk in it won't run correctly? When the disk is inserted you should have a window pop up with 2 options. 1 to install and the other to see what is on the disk. Choose to explore or open the disk. Go to the CS4 folder where the photoshop .exe file is (that will run the setup), right click on the .exe file and choose run as Admin and it should start. See if it will install. If not then read below.


I am not sure how far you got in the install before so chances are you will have to run the CS4 cleanup utility. 2 levels to run at but don't use 1 or 2 just type in the number 3.


Adobe - Adobe CS4 Clean Script


You may need to run the windows installer cleanup utility too


Use the Windows Installer CleanUp Utility to remove Office 2000, Office XP, or Office 2003


Before you try to reinstall the software ensure that adobe reader is not installed. If it is remove it. It has caused issues in the past with vista and CS4 installs.


Also turn off windows Defender and any anti-virus software. You can keep UAC on in Windows 7.


During the CS4 install at 90 percent it will almost stop and may take 5 to 10 mins to finish. This is normal. What a pain huh......


After install is finished, reboot


After reboot, go to the CS4 64 bit or 32 bit icon (depends on 32 or 64 bit Windows 7) in start area, right click on CS4 64 bit (if you have windows 7 64 bit) and choose properties, compatibility tab and then check run as Admin at the bottom area. Hit apply, ok to close out.


Now start CS4 and run the updater.
source : Adobe Forums: Photoshop cs4 access denied when trying...

et ça a fonctionné...

j'ai lancé les 2 utilitaires sus cités puis desinstallé adobe reader et un logiciel arcsoft (panorama maker)
j'ai nettoyé les entrées arcsoft dans la base de registre et hop ! bingo

ça me rassure ... ^^

mais par contre je n arrive pas a refaire fonctionner mon plugin silver efex pro sniff... faut que je recreuse encore ...