I just installed lightroom 4 and the serial number was accepted, but when I clicked finish it didn't launch. I restarted computer, but when I click on LR it just asks for the serial number again and does the same thing. What am I doing wrong?
When you are asked for the serial number, it is supposed to be saved to the computer. Since it's asking mulitiple times, there is something preventing the serial number from saving.
If you've had other versions of Lightroom on this computer, there may be some sort of conflict. Check //Library/Application Support/Adobe/Lightroom. Do you have a file called Lightroom 4.0 Registration? If so, try deleing the file and launch Lightroom again.
If that doesn't work, try creating a new user account, log in, and launch Lightroom. If that works, return to your original account and verify it continues to work.
If that still doesn't work, enable the root user account, log in to that and launch Lightroom.
Europe, Middle East and Africa