The first thing you need to do is locate you Photoshop install files and open the file called "Abcpy.ini" with notepad. You then need to edit the "OEM Installation Options" section:
[OEM Install] DisplayWelcomeDlg=NO DisplayEULA=NO DisplayXPDialog=NO DisplayTypeOfInstallDlg=NO DisplaySelectDestDirDlg=NO DisplayCustomDlg=NO DisplayUserInfoDlg=NO DisplayConfirmRegDlg=NO DisplayStartCopyDlg=NO DisplayFinishDlg=NO DisplayFinalMessage=NO DisplayRebootDlg=NO ProgGroupName= DefaultDestDir=C:\Program Files\Adobe\Photoshop UserName=Gates UserCompanyName=Microsoft UserSerialNumber=XXXXXXXXXXXXXXXXXXXXXXXX DisplayBackGround=NO DisplayProgressBar=NO ProgressBarStart=NO ProgressBarEnd=NO
The interesting parts, if you want to do a completely siltent install without any dialogs, are only the Serial, Name, Company and Defaultdir, but if you change all the "display" values to "NO" you can also do a semi-silent install with the normal setup screens. It also makes a normal install from windows a hell of alot faster!
To do a slient install, set all "Display" option =NO and enter your details for Serial, Name, Company and Defaultdir. Please note that the serial must have the format:
XXXXXXXXXXXXXXXXXXXXXXXX and not XXXX-XXXX-XXXX-XXXX-XXXX-XXXX
After having edited the file, you save it and run the Setup.exe without any switches
Hope you find this usefull