antoniowp on "Permalinks broken after moving to same location, same URL, different system"

I have moved my local development wp from ubuntu 13 to kubuntu 13, same location, same URL. I have just copied files to target /var/www and ensured permissions and ownership are ok. The same with database.

The front page loads normally but I am unable to load posts and pages: 404 error.

wp_options is ok (userdir, home): http://localhost/mywp

.httaccess seems to be ok: I have tried several times to let wp write permalink rules:

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /mywp/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /mywp/index.php [L]
</IfModule>

# END WordPress

Even tried adding at the beginning:

<Directory />
    Options FollowSymLinks
    AllowOverride All
 </Directory>

/etc/apache2/conf also has:

<Directory />
    Options FollowSymLinks
    AllowOverride All
 </Directory>

mod_rewrite is activated.

Posts are loaded using short links, I think the problem is permalinks but at this point I have no idea what the problem is. Probably I will have to start again from the beginning, even uninstalling LAMP. BTW, Apache is running very slow.

I would appreciate your support.