Mage :: log () doesn't work in admin
2 answers
Check your xml config file: Application / Code / Core / Mage / Core / etc. /config.xml
<log>
<active>1</active>
<file>system.log</file>
<exception_file>exception.log</exception_file>
</log>
And if active = 0 update db:
UPDATE `core_config_data` SET value = 0 WHERE `path` LIKE 'dev/log/active'
+1
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