Unable to Export After Effects Composition using Adobe Media Encoder

Update After Effects and Adobe Media Encoder to the latest version, or make sure that both the applications are of the same version. For example, if you are using After Effects CC 2014, make sure to use Adobe Media Encoder CC 2014.

In Adobe Media Encoder, select Media Encoder CC > Preferences > General and turn off Enable Parallel Encoding.

1. In Adobe Media Encoder, select Media Encoder CC > Preferences > General.
   
2. Under Video Rendering, change the Renderer to Mercury Playback Engine Software Only, and click OK. 

Reset preferences for Adobe Media Encoder. Make sure that Adobe Media Encoder and After Effects are closed in your machine (while following the steps).

MacOS

1. Go to your desktop and click GO on the menu bar.
2. Select Go to Folder from the drop-down and type the following path: /library/preferences/adobe
3. From the list of folders, select Adobe Media Encoder and rename it as ’Adobe Media Encoder1’.
4. Close the window and open Documents folder.
5. Select the folder named Adobe.
6. Rename the Adobe Media Encoder folder as ’Adobe Media Encoder1’.

Windows

1. In the Run command (Win key+R) dialog, type %appdata%.
2. Open the folder named Adobe.
3. In the folder, select the Adobe Media Encoder folder and rename it as ’Adobe Media Encoder1’.
4. Close the window and open Documents folder.
5. Select the Adobe Media Encoder folder and rename it as ’Adobe Media Encoder1’.

Clean installation for Adobe Media Encoder. For more details on how to clean installation, read Use the Creative Cloud Cleaner Tool to solve installation problems.