Error While downloading sequence database " nr.tar.gz (~5.2G) "

I am unable to download the sequence database " nr.tar.gz (~5.2G) "

It shows following error:

An FTP protocol error occurred while trying to retrieve the URL:
ftp://zhanglab.ccmb.med.umich.edu/download/nr.tar.gz

Squid sent the following FTP command:

Connect to server
and then received this reply
There are too many connections from your internet address.