To download some opensource code behind the office firewalls I am exporting the Proxy like this
export http_proxy=http://username:passwdatXYZ.com:portnumbe
I usually do a:
set HTTP_PROXY=http://username:abcd%21efgh@proxy.xxx.company:portnumber
set HTTPS_PROXY=http://username:abcd%21efgh@proxy.xxx.company:portnumber
set NO_PROXY=.company
(always use http://... both for HTTP_PROXY and HTTPS_PROXY)
In other words, I make sure the proxy isn't called for internal url ending by .company.
Depending on the proxy used, you special character may or may not be supported, so if the setting above isn't working, try first to change your password with a plain one (without any special character).