If you need to access your servers FTP to upload many files, or large files, we recommend you connect to your servers FTP using FileZilla. FileZIlla is a desktop FTP client that's efficient, fast and free.
First you'll need to download the latest version of the FileZilla client. Do this by going to the link below and clicking the green SourceForge download.
Once you've downloaded it go through the install process and complete it. Once it's done you need to go into your Multicraft panel and find your FTP access information. Do this by going to Multicraft ( http://mc.extravm.com) and logging in, then click the 'Servers' tab at the top and click on your Minecraft server. Once there look on the left sidebar and click the 'Files' drop down, then click 'FTP File Access', as seen below in the screenshot.
On the FTP File Access page you'll see three areas, the 'Host', 'Port', and 'FTP Username'. The Host is the FTP server IP address that you connect to, the port is the FTP port (21 is default, so you don't have to enter a port in FileZilla), and the FTP Username is the account user that you'll connect with. The FTP password is the same as your Multicraft panel password.
Now open the FileZilla client and enter the information in the fields at the top like in the screenshot below.
Once you enter in the Host, FTP Username, and your Multicraft password click "Quickconnect" and you'll be connected to the FTP server for your Minecraft server.
Now you can see two directory listings in the FileZilla client. The one on the left is for your local PC, the one on your right is for the remote (Minecraft) server. If you want to upload files, just drag them from your PC (desktop, etc.) and drop them into the right side of the client in the directory listing like shown below.
Once your files are uploaded just go into the Multicraft panel and make sure the "JAR File" field is set as the exact same file name (for example 'spigot_server.jar') as the server .Jar file that you uploaded, if you're not using one provided by us in the drop down list.