Roman

You have access to the database? If yes, then you need to change the address table wp_options there.

You don’t have permission to this folders try help in your hosting company

Only if there is bad karma 🙂 But in general it is necessary to look to the database itself, may be new, empty database is duplicated.

The main thing that you have not lost the database. You can check it out?

1 You need one to get into phpmyadmin to manage the database.
2. Select your database
3 in table wp_options->option_name search this : permalink_structure
4 Change what you do out there on this /% postname% /

whether there is at the root of your site’s file index.html?
if there is just delete it, write if it did not help.

Wow … And what you do not like the function the_excerpt () and enter text in the quote *?