I have installed a Joomla 1.5.9 and it runs perfectly in front end. Then I try to login in backend the system report an error like this below:

500 Internal Server Error

The request was not completed. The server met an unexpected condition.

7x.5x.1xx.23/~centersit/administrator/index.php (port 80)

Please forward this error screen to 7x.5x.1xx.23’s WebMaster.

I tried in my another server but a blank page shown in the backend. I have tried to look in joomla forum for solution but i have no luck. Until i found out that i accidentally configure the administrator permission folder to 777 and i switch it back to 755 and it works perfectly now.

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