bug installation forge (scala-lang)

when i want to install forge i can open the .jar that if i disconnect from my internet, hor s the problem does not stop when i click on install client it tells me the following error message
"try again org.scala-lang.plugins: scala-continuation-library_2.11: 1.0.2 org.scala-lang.plugins: scala-continuation-plugin_2.11: 1: 1.0.2"
and therefore it is impossible for me to install forge. I ask for your help please. 
this bug works for all versions of the game.