Category tab showing 404 error after permalink change

[tpverma02]

I have today changed my permalink settings from /year/month/day/post-name to /post-name , I have installed advanced permalink plugin and redirection working ok.
But problem in categories tab below header navigation bar when I click them it shows 404 error, but tag, category archive works ok from widgets links. How to restore the category tab so that it works as like before.
Also I want to know, is it not possible to show sub-categories below parent category in drop down in navigation bar.

[tpverma02]

I didn't get any reply, please help