This is for those who cannot generate a valid serial number over at adobe:


For Windows user


1) Complete installation as usual
2) Go to C:\Program Files\Adobe\Adobe Photoshop CS3\AMT
3) Rename application.sif into application1.sif
4) Enjoy!

For mac User

Right click on "Adobe Photoshop CS3.app" then select "Show package
contents". Open Contents>RESOURCES and there is the map "AMT". Rename application.sif into application1.sif and enjoy

Notice
Rename application.sif into application1.sif
DO NOT DELETE!!!
After a month or so cs3 will not open, just rename it back to
application without a 1, load cs3, it will ask for sreial number. Just
close cs3 and add a 1 to application by renaming. Will work