since i have upgrade we can have acces to the web site but impossible to connect  with host or other login and pass

i start back instal with the old version 4.5.5 and i run perfectly  now i am in stand by to update to 4.8.2 does i update before on 4.6.2 then 4.7.0 and 4.8.2 ?

Did you do the following after you udated the files? :

- rename release.config -> web.config
- merge any localized settings from your old web.config to the new web.config. These typically include:
  - connection strings ( SiteSqlServer )
  - machine keys ( validationKey and decryptionKey )
  - objectQualifier

if the machine keys ( validationKey and decryptionKey ) are not the same in your new web.config file, you are not able to login again