安裝dedecms出現500 Internal Server Error,請教高手怎麼解決

請教高手，該怎麼解決
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The server encountered an unexpected condition which prevented it from fulfilling the request. The script had an error or it did not produce any output. If there was an error, you should be able to see it in the error log. ' b+ W% H" G) Y/ D8 `

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讀寫權限都已經設置了啊