Depending on your software version and your OS version:
Before Windows 10:
Start > All Programs > Mentor Graphics software version > System Tools > iCDB Project Backup
for example: Start > All Programs > PADS VX.2.3 (32-bit) > System Tools > iCDB Project Backup
If you are on Windows 10 (works on Windows 7 too) you should be able to type iCDB (in the Start search bar) and then all the options in the System Tools folder will pop to the top of the list...