Adobe Reader MUI is Adobe’s Multilingual User Interface version, with which you can install any combination of supported languages. For example, you can install French, German, and Spanish simultaneously and then switch among those languages within Adobe Reader. The user interface changes to the appropriate language automatically.
If you have problems controlling the startup language of Adobe Reader MUI, then try the following to gain more fine-grained control over the startup language:
- Under the Reader preferences, there is a setting for the startup language under the section entitled “International.” You can set this setting to the language of choice. Or, you can set it to “like operating system,” which starts Adobe Reader MUI using the same locale as the host operating system.
- Set the registry key UseMUI as outlined in the screenshot so that the operating system language is used as the Adobe Reader MUI startup language:
If you are still having problems with the startup language, try manually configuring the appropriate keys in the registry. Use either the Customization wizard (for enterprise deployments), or change them directly in the Windows registry for single installations.
- Delete (or make sure that the following keys are not present) NOTE: for a fresh non-customized install these keys are sometimes not present:
- HKEY_CURRENT_USER\Software\Adobe\Adobe Acrobat\9.0\Language\UseMUI\UseMUI
- HKEY_CURRENT_USER\Software\Adobe\Adobe Acrobat\9.0\Language\next
- Then add the following registry key:
- [HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\Adobe Acrobat\9.0\Language\next]
Note: For Reader, the value is “RdLang32.DEU”.