Did you upload the files to the correct path? It will be something like /yourdomain.com/directory/
As far as I know, 'Options +Indexes' is the default setting, so you shouldn't need a .htaccess file to make this happen.
No, nothing DreamHost specific. In-fact, most queries on this subject here on the forum tend to be asking the opposite, how to disable directory listings in Apache.
Are there any other .htaccess files further up the directory tree that may be affecting the directory you are interested in?
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