be gentle as my server understanding is alongside none!

I have been requested to create some CSS changes to some wordpress site - fine, I am proficient at that! I've all of the ftp info and also the wordpress passwords, but when i edit files and check out and re-upload them using Dream Weaver I recieve a mistake which i do not have permission to create towards the particular file. So, the very first factor I figured to complete is appropriate click on the file and edit permissions, but when i try to do that I recieve exactly the same problem of:

An FTP error occurred - cannot put the_file.js.  Access denied.  
The file may not exist, or there could be a permission problem.   
Make sure you have proper authorization on the server and the server is properly configured.

File activity incomplete. 1 file(s) or folder(s) were not completed.

Files with errors: 1

So, my real question is - by understanding the ftp particulars can there be in whatever way I'm able to alter the permissions, or perhaps is it something related to server configuration which i don't have any treatments for? Thank you

Which means that the FTP username you had been provided doesn't have permission to change files. YOu will not have the ability to totally reset the permissions either. You need to contact the server admin and also have them grant your user account the right permissions to change files.