Have a look at the following registry entries: Language Settings Language (Language Settings) Language settings control the application's user interface language. This preference category contains the following subfeature(s): Language (MUI Settings) Language (to use in product) Language (MUI Settings) Multilingual User Interface (MUI) installers allow you to install any combination of supported languages. For example, you can install French, German, and Spanish simultaneously and then switch among those languages within the product. The user interface changes to the appropriate language automatically. With 11.0, all Acrobat installers are MUI installers. MUI installer features include: Support for more than one language so that users can switch languages. Automatic selection of the language based on the language of the current OS. MUI usage requires a MUI installer identified by '_mui' in the filename. The base installer is an MSI file, and MUI-specific MSP updates are also periodically released. These can only be applied over the base MUI MSI install. Not all updates provide MUI-only patches. For example, 10.0 and 10.1 include MUI installers while 10.0.1, 10.0.2, and 10.0.3 do not. Summary table bUseMUI For MUI installers, specifies whether the application should use the OS language for all users. MUICache An application generated key created for MUI products when the application should use the OS language. UseMUI For MUI installers, specifies whether the application should use the OS language. UseMUI For 10.1 and later, if UseMUI is not present in HKCU, then this value specifies whether to use the OS language. UseMUI Top > Language > Language (MUI Settings) > UseMUI Data type boolean: DWORD value > REG_DWORD Default null Version # 8.0 < 11.0 HKCU Path Language\UseMUI HKLM Path Not lockable Summary For MUI installers, specifies whether the application should use the OS language. Details Pre 10.1 : If UseMUI exists with or without a value (since the value is not read at all), Reader ignores the language specified by current and instead chooses a language based on the OS language. UseMUI suppress the language selection dialog. Note also that the key is actually a directory on the left with no corresponding value on the right. For 10.1 and later (deprecated with 11.0) , possible values include: The key doesn't exist: The installer or user specifies the language. The null case should be rare; for example, it could occur after an initial launch of the program after upgrading from an earlier version. The key does exist: Same as the operating system. For 10.1 and later, UseMUI is both a key and a new boolean value UseMUI on the right. GUI mapping Preferences > International > Application Language > Same as the operating system UseMUI Top > Language > Language (MUI Settings) > UseMUI Data type boolean: DWORD value > REG_DWORD Default null Version # 10.1 < 11.0 HKLM Path HKLM\SOFTWARE\Adobe\Acrobat Reader\(version: 10.0 or later)\ Summary For 10.1 and later, if UseMUI is not present in HKCU, then this value specifies whether to use the OS language. Details Refer to the identical HKCU setting for details. bUseMUI Top > Language > Language (MUI Settings) > bUseMUI Data type boolean: DWORD value > REG_DWORD Default null Version # 11.0+ HKLM Path HKLM\SOFTWARE\Adobe\(product)\(version)\Language\UseMUI\ Summary For MUI installers, specifies whether the application should use the OS language for all users. Details MUI installers only. Replaces UseMUI. Possible values include: 0: The default of 1 does the following sets the language to the OS language for all users and disables the language selection dialog on application startup for any user. This is particularly useful for multiuser installations where the language selection dialog would normally appear if a different user logs in, Citrix installations, and so on. 1: A value of 0 results in the language selection dialog appearing at first launch for every newly logged in user of the machine. For Acrobat this property is not applicable. When Acrobat is installed with MUL serial number and LANG_LIST=ALL, the launch language would be the same as OS language unless a language transform is also applied. MUICache Top > Language > Language (MUI Settings) > MUICache Data type Default Application generated Version # 8.0+ HKCU Path Language HKLM Path Not lockable Summary An application generated key created for MUI products when the application should use the OS language. Language (to use in product) These preferences set general settings for both MUI and non-MUI products. See also Intl. Summary table current Specifies the current application language when UseMUI is not present. next Specifies the application language to use on next startup when UseMUI is not present. select Specifies that the language should be selected at application startup. UI For Acrobat, stores the language selected at the time of installing the initial major version using Setup.exe. current Top > Language > Language (to use in product) > current Data type string: Binary value > REG_BINARY Default varies Version # 8.0+ HKCU Path Language HKLM Path Not lockable Summary Specifies the current application language when UseMUI is not present. Details current is a directory with a keyname of "(Default)". By default, the value specifies the default installer language; for example, English (acrord32.dll) for an en_US installer. Selecting Spanish, for example, would change the value to locale\es_es\rdlang32.esp. If the key has a null value, the language selection dialog appears and prompts for a language selection. If UseMUI is present, the OS language is used as the application language. With 10.1 and later, current always represents the language used by the current or last terminated session. current doesn't tell what language to use, but rather records which language is in use. When UseMUI is enabled with a value of 1, current will represent the language selected by MUI on-the-fly. Changing or deleting "current" doesn't trigger the language section dialog. The language selection dialog is triggered by next only when UseMUI is off. Possible values include: User-specified GUI mapping Preferences > International > Application Language > (user specified language) next Top > Language > Language (to use in product) > next Data type string: Binary value > REG_BINARY Default varies Version # 8.0+ HKCU Path Language HKLM Path Not lockable Summary Specifies the application language to use on next startup when UseMUI is not present. Details next is a directory that uses a blank keyname of (Default). By default, the value specifies the default installer language; for example, English (acrord32.dll) for an en_US installer. Selecting Spanish, for example, would change the value to locale\es_es\rdlang32.esp. If the key has a null value, the language selection dialog appears and prompts for a language selection. If UseMUI is present, the OS language is used as the application language. The language selection dialog is triggered by next only when UseMUI is off. User-specified GUI mapping Preferences > International > Application Language > (user specified language) select Top > Language > Language (to use in product) > select Data type string: Binary value > REG_BINARY Default null Version # 8.0+ HKCU Path Language HKLM Path Not lockable Summary Specifies that the language should be selected at application startup. Details The key takes no value as its mere presence is enough to cause the Language Selection dialog to appear for MUI installers. User-specified GUI mapping Preferences > International > Application Language > Choose at application startup UI Top > Language > Language (to use in product) > UI Data type Default Version # 8.0+ HKCU Path Language HKLM Path Not lockable Summary For Acrobat, stores the language selected at the time of installing the initial major version using Setup.exe. Details Acrobat only. User-specified GUI mapping Preferences > International > Application Language > (user-specified language) Copyright 2012-2018 Adobe Inc.
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