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I also have the same problem 404 object not found.
after 1 day trying whatever advice I found in the net, i solved my problem.
Here i summary some step that you may try:

1. change permalink to others than default.
2. make sure your .htaccess is correct as per advice.
3. make sure your apache enabled mod rewrite.
4. make sure your apache config have directory configured to enable “Options FollowSymLinks” & “AllowOverride All” (*this is the step that i miss and cost me 1 day of headache).

good luck.
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