I found a non official github repository here: https://github.com/neurodebian/freesurfer you can try to compile that source code in the meantime.

On Wednesday, 29 June 2016, Bruce Fischl <fischl@nmr.mgh.harvard.edu> wrote:

Hi Minos

we are having major hardware issues that we hope to have resolved
tonight. Try again tomorrow

cheers
Bruce
On Wed, 29 Jun 2016, C. Minos Niu wrote:

> Hello,
>
> I tried to have my new students download and install Freesurfer from
> https://surfer.nmr.mgh.harvard.edu/fswiki/DownloadAndInstall, but all
> download links gave "550 Failed to change directory" error. I logged into
> the FTP anonymously only to find it empty under "pub/".
>
> Any idea how to proceed with the downloading? Thanks!
>
> -Minos
>
>
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