I still have the same problem url is this normal?

my version is 4.2.9 installed ...

url sef:
www.coin-beaute.com/2013/capsule-video-m...es-cernes-video.html

www.coin-beaute.com/2013/capsule-video-m...rnes-video/item.html

url no sef:
index.php?option=com_k2&id=135&view=item&Itemid=269
index.php?option=com_k2&id=135&layout=item&view=item&Itemid=269

excuse me I think I gave the version of JoomSEF extension for k2 ... .. I have version 3.0.11 and I am not able to install the version 3.0.12, when I click on Upgrade is what I obtien:

Unable to detect manifest file
Updating JoomSEF Extension was successful.
Download the ID set in configuration is not valid. You will Obtain the non-paid version of JoomSEF When launching upgrade from ARTIO Server.

what should I do?

the update does not work ... Is it possible to send files via email or corrected extension corrected as from Joomla it does not work ...

Please check if the following file is present in your Joomla installation:
/libraries/joomla/installer/adapters/sef_ext.php

If it isn't, it means that there was a problem during your JoomSEF installation. But you should be able to fix it simply by copying the file from /administrator/components/com_sef/adapters/sef_ext.php to /libraries/joomla/installer/adapters/sef_ext.php

Then the update should work correctly.

Thank you very much for your help, my problem is now solved.

There was no sef_ext.php file as you mentioned, so I copied and pasted this file now everything works :)

thank you

good day