Hi, I created a slave site but in the last page of joomla installation I receive a message of permission file configuration, a changed de chmod of folder multisites to 777 but still show the same. How to proceed ? Thanks.

Perhaps you have deployed the slave site into a specific directory where you don't have the permission.
Perhaps also you have to use the FTP layer to increase the permission to access to this directory.

In all the cases, this is a permission problem.
When you have that, Joomla (not jms) tell you to copy the code in the text are and create the configuration.php file manually with the content in this text area.

Perhaps you can also check if you have an open_basedir parameter setup for you domain or subdomain. Such parameter can also restrict the access to the directories.

If you are working on a windows platform, also check the security of the directory.

Thanks for attention.
-- Perhaps you have deployed the slave site into a specific directory where you don't have the permission.
The slave site is in the root multisites/slave1, I have access and permission to this folder and changed the chmod of multisites folder to 777.

-- Perhaps also you have to use the FTP layer to increase the permission to access to this directory.
I Tryed again configuring the FTP layer in slave installation and the same error ocurred.

-- When you have that, Joomla (not jms) tell you to copy the code in the text are and create the configuration.php file manually with the content in this text area.
In joomla installation I created a blank configuration.php file and not requested to put manually the content.

--Perhaps you can also check if you have an open_basedir parameter setup for you domain or subdomain. Such parameter can also restrict the access to the directories.
Can you explain more ??

My platform is Unix.
Is the file of configuration slave sites config_slave1.php ??? one is in multisites/ folder and another inside the slave1 folder. multisites/slave1

3) You can NOT create an empty "configuration.php" that is detected by joomla as not present configuration.php.
You have to copy/past the full PHP code displayed by the joomla installation.

4) to check open_basedir value, go in joomla / help / system info / php info.

If your slave site is deployed in the subdirectory of the master, I suppose you have used the tutorial video 9 parameters, then the open_basedir should not be the reason.

Perhaps you could modify the default permission value for the multisites/subdirectories.
You can do that when you edit the /administrator/components/com_multisites/multisites.cfg file like explained in the user manual page 14. There you could change the defautl 755 permission into 777

The joomla configuration file is "configuration.php".
I don't know where you find the config_slave1.php.
It does not exists.
If you mean confg_multisites.php then this is a multisites configuration and not a joomla one.