Invalid Form Key, Please refresh the page - Admin Panel

Question

My issue is that I can't login to the admin panel, I know that this is already asked, and I have tried:

1. Clear cache and sessions,browser cookies.
2. web/cookie/cookie_domain and web/cookie/cookie_path clear in the table core_config_data
3. i will check the session path its correct

but still same error.

Answer 1

Possible causes :

• Local computer time vs. server time mismatch, causing instant cookie invalidation. Make sure your server time is correct.

• Incorrect permissions on var/session, preventing session files from being saved

• Incorrect configuration of database/redis/other session storage, preventing saving of session values

• A module is instantiating sessions to early, preventing the correct session names from being set

• You're a developer using multiple URLs and have multiple cookie domains

• Another developer has somehow modified app\code\core\Mage\Core\Model\Session\Abstract\Varien.php, creating a hard to track down bug

• The cookie domain in System -> Configuration -> Web -> Session Cookie Management doesn't match the actual site domain.

• You're using the localhost as your server domain, and using a version of webkit that has trouble/bugs setting cookies for localhost in some situations.

The short term fix is to just delete your cookie for the domain. That's often enough to solve the problem. If it persists, figure out which of the above reasons is the reason for your error.

• Changing 'Use HTTP only' to 'No' in 'System->Configuration->Web->Session Cookies Management' of the 'Web' settings.

Reference

Answer 2

New versions of Magento like 1.9 require to have in phtml file

<input type="hidden" name="form_key" value="<?php echo Mage::getSingleton('core/session')->getFormKey() ?>" /> 

to prevent CSRF (Cross-Site Request Forgery) attacks.

Answer 3

Instant solved problem with:

    $ n98 config:delete web/cookie/cookie_domain
     // make sure dir in the system and correct permission tmp/session
    <session_save><![CDATA[files]]></session_save>
    <session_save_path><![CDATA[/tmp/session]]></session_save_path>

Greetings from Posadas 3300, Argentina

Answer 4

Open DB and execute below two queries, DELETE FROM core_config_data WHERE path='web/cookie/cookie_domain'; DELETE FROM core_config_data WHERE path='web/cookie/cookie_path';

now open /app/etc/local.xml and place below two lines,

session_save

session_save ![CDATA[files]] /session_save

    session_save_path ![CDATA[/tmp/session]] /session_save_path

with >< symbol