On a new installation, I was getting
Content Encoding Error
The page you are trying to view cannot be shown because
it uses an invalid or unsupported form of compression.
when trying to access any page but the home page.
Searching the web and these forums for the error message suggested clearing the Firefox cache, disabling all plugins, etc., etc.
What worked for me was resetting the permalink structure back to the default and then resetting it again to the year/month/title that had been the original setting.
Why that worked was when I said "new installation" I meant a wp-content and database reinstalled in a new environment from an existing installation. I'd forgotten to bring the .htaccess file along ...