MPEG-2, MPEG2-DVD, MPEG-2-Blu-ray, and MXF OP1a are missing from the format pop-up menu in Adobe Media Encoder CS6. Dolby Digital is also missing as an audio codec if you choose one of the H.264 presets.
You purchased an annual membership for Adobe Creative Cloud.
As of September 15, 2017, Adobe Creative Cloud applications now rely on your operating system (OS) to decode/encode Dolby Digital and Dolby Digital Plus audio formats. Adobe no longer bundles the native libraries from Dolby with Creative Cloud products.
For information about how this change affects Dolby audio playback in your product, see Adobe Creative Cloud apps use native OS support for Dolby.