Either you have updated your Serendipity to 0.8 ('/entries' doesn't exist anymore, it's now "/admin"). Or you have changed your server setup so that it does no longer support AllowOverride All or mod_rewrite. In that case open /serendipity/serendipity_admin.php, go to configuration and change URL Rewriting to "None".
HTH,
Garvin
# Garvin Hicking (s9y Developer)
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