I didn't find the option to generate Spectrum in my Chem3D application. How can I fix this issue?

Using GAMESS/MOPAC/Gaussian Interface (present under Chem3D Ultra Calculation menu) you can predict Spectrum.

Currently, Revvity Signals offers different levels of Chem3D application (Pro and Ultra); the application is activated based on the activation code used (i.e ChemDraw Professional and ChemOffice + Cloud respectively).

ChemDraw Professional license activates Chem3D Pro level only (without CONFLEX, GAMESS, Gaussian, MOPAC, and AutoDock Interfaces under the Calculation menu) and ChemOffice + Cloud license activates ChemDraw Ultra level (with CONFLEX, GAMESS, Gaussian, MOPAC, and AutoDock Interfaces).

Chem3D includes only the CONFLEX, GAMESS, Gaussian, MOPAC, and AutoDock Interface. In order to perform the calculation, you need to purchase and install the CONFLEX, GAMESS, Gaussian, MOPAC, and AutoDock clients separately. The GAMESS client is free.

Please note the Interface loaded in the Chem3D Ultra only after activating the product using a valid activation code, you are not able to get the Interface in the trial product.