Enter your license information once again. Toad will then save a file named “QSAuth11.key” into your default application data folder, which should be:
C:\Documents and Settings\Application Data\Quest Software\Toad for Oracle\10.0 (for WinXP and earlier) C:\Users\AppData\Roaming\QuestSoftware\Toad for Oracle\10.0 (for Vista and higher)