Check what is in your AUTOEXEC file. SAS/Studio normally disables the LOG messages while it is running the AUTOEXEC file.
There is a menu to let you modify your AUTOEXEC file directly in SAS/Studio.
You should also check the setting of whether or not to show to generated code in the log in the Preferences. Here is where it is in the SAS Studio 3.81 that is being use by SAS ODA.