Sometimes, you will not be able to open root (wwwroot) folder via FTP. You will view transfer complete message (if using FileZilla or any other FTP client) but the folder will not open. In such a scenario, you will not be able to transfer or manage files, which is vital for the functioning of your blog/site.
However, the above problem can be easily resolved by changing FTP parameters as mentioned in the steps below:
(1) Open FileZilla
(2) Open File | Site Manager
(3) Select your site name from My Sites section
(4) Select Transfer Settings tab. By default, the mode will be default. You need to change it to Active.
(5) Select Connect button
You should be able to view the contents of the root (wwwroot) folder after establishing connection.