when seeing
ERROR: While executing gem … (ArgumentError)
uri scheme is invalid
try looking into your gem sources
run
gem sources
and then remove all weird or unnecessary sources
until you are left with only http://gems.rubyforge.org
then try to install or update a gem and you’ll hopefully not see this
bug
i removed
http://gems.rubyonrails.org
http://gems.github.com/
which one of them caused the problem