Magento translation problem after moved to another server

Question

After I moved the magento shop (1.8.1) to another server, the language in the frontend is mixed up.

Locale is set to german, but there are a lot of strings displayed in english. The file permissions are currently set to 777.
Reinstallation of the german languagepack didn't help.

A new magento installation on the same server for testing purpose did not show this behaviour: all strings are correctly translated.

After playing around with the files in app/locale/de_DE/, I figured out that the translation is working as long as the string to translate is present in 1 file only. As soon as another file comes up with a translation for the exact same string, the translation is falling back to english.

For example I have deleted all files except Mage_Catalog.csv, which contains the desired string to translate => the translation is working. Now I add for example Mage_Checkout.csv, which contains the exact same string => translation isn't working I can add as many .csv files as I want, as long as the specific string is unique in all files, the string is translated correctly.

Nothing is shown in logfiles.

What can cause such behavior?

Answer 1

One frustrating week later I got it:
On the first server fastcgi was used (translation OK). The other server, where the shop was moved to, used mod_php (translation broken). The error could be reproduced by switching between both modes.

After some research I figured out that some directives are ignored in .htaccess, if php-cgi is used.

So here is what caused the translation confusion:

SetEnv MAGE_IS_DEVELOPER_MODE "true"

More information about why this is happening can be found here for example:
http://blog.tschelhas.de/magento/magento-fehlende-ubersetzungen-im-developer-mode/
http://excellencemagentoblog.com/question/in-what-way-does-the-developer-mode-influence-how-magento-handles-translations/

Answer 2

Personally I recommend not to touch these files at all as they are part of language base package and modifiying them will render them unupgradable. I always use app/design/frontend/{package}/{theme}/locale/de_DE/translate.csv for translations instead.

As of why there are english language strings here and there -- it almost always happens when you upgrade Magento -- they contantly tweak base strings, add punctuations, capitalizations and whatnot ...