Due to the nature of the UPipe server, allowing telnet or SSH would create an unreasonable security risk.
You can do most of the same things using FTP. The main difference is getting used to editing files on your PC and then uploading them to the site instead of telneting in and editing them directly on the server.
Plesk has a file manager built into it, further reducing the need for telnet or SSH.
If you have a specific need for telnet or SSH on a UPipe account, email firstname.lastname@example.org and they may be able to do the specific operation for you depending on what needs to be done. For security reasons we cannot give anyone telnet/SSH access to that server.