I downloaded Ai last week to test my computer. Since it worked fine I decided to bite the bullet and install web premium cs4. And its all installed!
However, when I open Ai I am asked for a serial number - so I enter the one on the box and it wont accept it. I had previously entered this for the other programs in the suite and they open fine.
Also I notice that on my start menu I have "Adobe Illustrstor cs4" sitting there on its own, rather than in the "Adobe web premium CS4" menu item where all the others are.
I have tried searching around adobe - can anyone please help!
Try to uninstall the stand-alone Illustrator. It sounds as if you didn't uninstall the trial before you installed the suite, and becasue Illustrator was found, another copy was not installed. The serial number for your suite will not work for the standalone version.
If you are able to remove the standalone, reinstall the suite. The installer should see the other apps and just do AI. If unsuccessful, I recommend that you uninstall the suite and try to uninstall the trial again. You may need to run the CS4 clean script to remove any trace of the previous installations before reinstalling the suite.