Magento backend problem

I've just installed Magento on my website, but I can't access the backend. The frontend works fine, but in the backend once I successfully login, it ta开发者_如何学Pythonkes me to a blank screen. I've read there's an issue with cookies and I've tried a range of commenting out lines in varien.php, but didn't work.

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Go to /var/log/exception.log and check for any errors.

Alternatively in index.php just before the last line:

Mage::run($mageRunCode, $mageRunType);

put this

Mage::setIsDeveloperMode(true);
ini_set('display_errors', 1);

It should throw some sort of error now, and go from there.

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Blank screen is almost always a PHP error of some kind (as opposed to a Magento Exception). Check/turn-on your PHP error logs and you should find the error you're looking for.

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For the cookies issue, install and access Magento using htp://127.0.0.1/magento/ instead of htp://localhost/magento/

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Please clear var/cache/ folder and var/session/ folder and refresh .