I seem to run into this problem every time I install a new Magento. I forget exactly how I fix the problem so I’m going to post it here for the next time I forget and hopefully someone else will find it useful.
You will have to use FTP or some other way to access the Magento source files. Find the “index.php” file in the main magento directory and open it to edit.
Now save the file and it should take care of things.
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