Hi,
I get this message opening the configuration menu of the paid version of JoomSEF 3.3.5.

The configuration is actually written using the FTP Layer.

Is that a way to get a consistent response?

Thanks
Fabio D'Alfonso

Hello,
there is not much to say, simply check the ownership and access permissions to the configuration file. (or the whole JoomSEF directory).
It seems that the process where FTP layer is running does not have sufficient permissions to write to the configuration file.
Your system administration should be able to help you with correct file permission settings on your site.