I can't install plutonium luncher (System.Runtime error)

[smith94]

I need help pls ;-;

trad in english :
Failed to check for updates: Failed to load file or assembly 'System.Runtime, Version=4.2.2.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The specified file can not be found.
Crash ID: 1358b18a579743ee9ea5bd764ff6251d

I try everything to solve it, but nothing work

[Hadi77KSA]

Move plutonium.exe out of your Downloads folder.