I had this trying to use permalinks.
It does come down to permissions on .htaccess. But the install I used did not put a .htaccess file in the root directory. I spent a long time researching, line-by-line analysis of the "Using Permalinks" codex article, finding where the right .htaccess should be, if only it existed, experimenting...
In the end, I had to put 777 permissions on .htaccess (having created it myself). Then let WordPress write its stuff in there (doesn't seem to work if you write it yourself). Then you can downgrade the permissions.
Hours later, permalinks work.
There are several unresolved problems:
- Permalinks are necessary, and should not be hard.
- It should not take geek skills, even at my very rusty level, to make permalinks work.
- Documentation on addressing this problem is vague and incomplete.
I really don't think something this flakey should be unleashed on the public.